If you find this page useful and would like to be notified of changes made to this page, start by inputting your email below.
powered by ChangeDetection
m |
m |
||
Line 316: | Line 316: | ||
| url = http://wellwiki.org/wiki/Texas_Oil_and_Gas_Data_Sources#Well_Production | | url = http://wellwiki.org/wiki/Texas_Oil_and_Gas_Data_Sources#Well_Production | ||
| accessdate = 2015-07-24 }}</ref> | | accessdate = 2015-07-24 }}</ref> | ||
− | ==References== | + | [[Category:Has Chemical Data]] |
+ | ==Chemical Data== | ||
+ | {| class="wikitable sortable" width="95%" | ||
+ | !scope="col" | HF Fluid Concentration | ||
+ | !scope="col" | Ingredient | ||
+ | !scope="col" | Additive Concentration | ||
+ | !scope="col" | Trade Name | ||
+ | !scope="col" | Purpose | ||
+ | !scope="col" | CAS number | ||
+ | !scope="col" | Supplier | ||
+ | |- | ||
+ | | 0.00375 | ||
+ | | Glutaraldehyde (Pentanediol) | ||
+ | | 15.0 | ||
+ | | ALPHA 114 | ||
+ | | Anti-Bacterial Agent | ||
+ | | 000111-30-8 | ||
+ | | BAKER HUGHES | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00125 | ||
+ | | Dimethyl benzyl ammonium chloride | ||
+ | | 5.0 | ||
+ | | ALPHA 114 | ||
+ | | Anti-Bacterial Agent | ||
+ | | 000139-08-2 | ||
+ | | BAKER HUGHES | ||
+ | |- | ||
+ | |- | ||
+ | | 0.6939 | ||
+ | | Water | ||
+ | | 85.0 | ||
+ | | 15 hcl | ||
+ | | Acid | ||
+ | | 007732-18-5 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.12245 | ||
+ | | Hydrochloric Acid | ||
+ | | 15.0 | ||
+ | | 15 hcl | ||
+ | | Acid | ||
+ | | 007647-01-0 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00089 | ||
+ | | Proprietary Cured Acrylic Resin (EnCap HP) | ||
+ | | 25.0 | ||
+ | | EnCap HP | ||
+ | | Breaker | ||
+ | | TRADE SECRET | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00213 | ||
+ | | Ammonium Persulfate | ||
+ | | 60.0 | ||
+ | | EnCap HP | ||
+ | | Breaker | ||
+ | | 007727-54-0 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 88.2022 | ||
+ | | Water | ||
+ | | 100.0 | ||
+ | | Fresh Water | ||
+ | | Carrier/Base Fluid | ||
+ | | 007732-18-5 | ||
+ | | CHESAPEAKE ENERGY | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00097 | ||
+ | | Diethylene Glycol | ||
+ | | 5.0 | ||
+ | | SCALETROL 7208 | ||
+ | | Scale Inhibitor | ||
+ | | 000111-46-6 | ||
+ | | BAKER HUGHES | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00485 | ||
+ | | Ethylene Glycol | ||
+ | | 25.0 | ||
+ | | SCALETROL 7208 | ||
+ | | Scale Inhibitor | ||
+ | | 000107-21-1 | ||
+ | | BAKER HUGHES | ||
+ | |- | ||
+ | |- | ||
+ | | 0.08645 | ||
+ | | Petroleum Distillate Hydrotreated Light | ||
+ | | 60.0 | ||
+ | | WG-111L | ||
+ | | Gelling Agent | ||
+ | | 064742-47-8 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.08645 | ||
+ | | Polysaccharide blend | ||
+ | | 60.0 | ||
+ | | WG-111L | ||
+ | | Gelling Agent | ||
+ | | NA | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.02798 | ||
+ | | Methanol (Methyl Alcohol) | ||
+ | | 0.0 | ||
+ | | ALPHA 114 | ||
+ | | BAKER HUGHES | ||
+ | | 000067-56-1 | ||
+ | | SCALETROL 7208 | ||
+ | |- | ||
+ | |- | ||
+ | | 0.02173 | ||
+ | | Sodium Chloride | ||
+ | | 0.0 | ||
+ | | ALPHA 114 | ||
+ | | BAKER HUGHES | ||
+ | | 007647-14-5 | ||
+ | | SCALETROL 7208 | ||
+ | |- | ||
+ | |- | ||
+ | | 0.02173 | ||
+ | | Proprietary Polyacrylate | ||
+ | | 0.0 | ||
+ | | ALPHA 114 | ||
+ | | BAKER HUGHES | ||
+ | | TRADE SECRET | ||
+ | | SCALETROL 7208 | ||
+ | |- | ||
+ | |- | ||
+ | | 0.04971 | ||
+ | | Water | ||
+ | | 0.0 | ||
+ | | ALPHA 114 | ||
+ | | BAKER HUGHES | ||
+ | | 007732-18-5 | ||
+ | | SCALETROL 7208 | ||
+ | |- | ||
+ | |- | ||
+ | | 71050.0 | ||
+ | | 2-Propenoic | ||
+ | | 0.0 | ||
+ | | ALPHA 114 | ||
+ | | BAKER HUGHES | ||
+ | | Polymer with Sodium | ||
+ | | SCALETROL 7208 | ||
+ | |- | ||
+ | |- | ||
+ | | 0.02173 | ||
+ | | Potassium Chloride | ||
+ | | 0.0 | ||
+ | | ALPHA 114 | ||
+ | | BAKER HUGHES | ||
+ | | 007447-40-7 | ||
+ | | SCALETROL 7208 | ||
+ | |- | ||
+ | |- | ||
+ | | 0.02798 | ||
+ | | Ethanol | ||
+ | | 0.0 | ||
+ | | ALPHA 114 | ||
+ | | BAKER HUGHES | ||
+ | | 000064-17-5 | ||
+ | | SCALETROL 7208 | ||
+ | |- | ||
+ | |- | ||
+ | | 7e-05 | ||
+ | | Methanol (Methyl Alcohol) | ||
+ | | 40.0 | ||
+ | | LAI-20 | ||
+ | | Corrosion Inhibitor | ||
+ | | 000067-56-1 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 1e-05 | ||
+ | | Propargyl Alcohol (2-Propynol) | ||
+ | | 8.0 | ||
+ | | LAI-20 | ||
+ | | Corrosion Inhibitor | ||
+ | | 000107-19-7 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.06456 | ||
+ | | Propylene Carbonate | ||
+ | | 0.0 | ||
+ | | FEA-20 | ||
+ | | LCL-21LTB | ||
+ | | 000108-32-7 | ||
+ | | LAI-20 | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00012 | ||
+ | | Proprietary Alcohol Ethoxylate Surfactants | ||
+ | | 0.0 | ||
+ | | FEA-20 | ||
+ | | LCL-21LTB | ||
+ | | TRADE SECRET | ||
+ | | LAI-20 | ||
+ | |- | ||
+ | |- | ||
+ | | 0.06456 | ||
+ | | Guar Gum | ||
+ | | 0.0 | ||
+ | | FEA-20 | ||
+ | | LCL-21LTB | ||
+ | | 009000-30-0 | ||
+ | | LAI-20 | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00012 | ||
+ | | Modified Thiourea Polymer | ||
+ | | 0.0 | ||
+ | | FEA-20 | ||
+ | | LCL-21LTB | ||
+ | | 068527-49-1 | ||
+ | | LAI-20 | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00012 | ||
+ | | Proprietary n-Olefin | ||
+ | | 0.0 | ||
+ | | FEA-20 | ||
+ | | LCL-21LTB | ||
+ | | TRADE SECRET | ||
+ | | LAI-20 | ||
+ | |- | ||
+ | |- | ||
+ | | 0.02964 | ||
+ | | Water | ||
+ | | 0.0 | ||
+ | | FEA-20 | ||
+ | | LCL-21LTB | ||
+ | | 007732-18-5 | ||
+ | | LAI-20 | ||
+ | |- | ||
+ | |- | ||
+ | | 0.06456 | ||
+ | | Sorbitan Trioleate | ||
+ | | 0.0 | ||
+ | | FEA-20 | ||
+ | | LCL-21LTB | ||
+ | | 026266-58-0 | ||
+ | | LAI-20 | ||
+ | |- | ||
+ | |- | ||
+ | | 0.06456 | ||
+ | | Modified Bentonite (Organophillic Clay) | ||
+ | | 0.0 | ||
+ | | FEA-20 | ||
+ | | LCL-21LTB | ||
+ | | 068953-58-2 | ||
+ | | LAI-20 | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00015 | ||
+ | | Proprietary Alcohol Alkoxylate | ||
+ | | 20.0 | ||
+ | | S-15 (Surfactant) | ||
+ | | Surfactant | ||
+ | | TRADE SECRET | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00015 | ||
+ | | Methanol (Methyl Alcohol) | ||
+ | | 20.0 | ||
+ | | S-15 (Surfactant) | ||
+ | | Surfactant | ||
+ | | 000067-56-1 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00174 | ||
+ | | Potassium Hydroxide | ||
+ | | 5.0 | ||
+ | | LCL-21LTB | ||
+ | | Cross Linker | ||
+ | | 001310-58-3 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.01046 | ||
+ | | Potassium Metaborate | ||
+ | | 30.0 | ||
+ | | LCL-21LTB | ||
+ | | Cross Linker | ||
+ | | 016481-66-6 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00349 | ||
+ | | Ethylene Glycol | ||
+ | | 10.0 | ||
+ | | LCL-21LTB | ||
+ | | Cross Linker | ||
+ | | 000107-21-1 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.01599 | ||
+ | | Petroleum Distillate Hydrotreated Light | ||
+ | | 60.0 | ||
+ | | FR-12 (Anionic Acrylamide) | ||
+ | | Friction Reducer | ||
+ | | 064742-47-8 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00053 | ||
+ | | Quaternary Ammonium Chloride (Ammonium Chloride) | ||
+ | | 2.0 | ||
+ | | FR-12 (Anionic Acrylamide) | ||
+ | | Friction Reducer | ||
+ | | 012125-02-9 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00068 | ||
+ | | Acetic acid | ||
+ | | 85.0 | ||
+ | | FEA-20 | ||
+ | | Iron Control Agent | ||
+ | | 000064-19-7 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 4e-05 | ||
+ | | Methanol (Methyl Alcohol) | ||
+ | | 5.0 | ||
+ | | FEA-20 | ||
+ | | Iron Control Agent | ||
+ | | 000067-56-1 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |- | ||
+ | | 0.00111 | ||
+ | | Ammonium Persulfate | ||
+ | | 100.0 | ||
+ | | WBO-1 (Oxidizer Breaker) | ||
+ | | Breaker | ||
+ | | 007727-54-0 | ||
+ | | TRICAN | ||
+ | |- | ||
+ | |} | ||
+ | For data sources see<ref>{{cite web | title = FracFocus Chemical Disclosure Registry |publisher = [http://www.fracfocusdata.org/DisclosureSearch/]| date = 2015-08-10 | url = http://wellwiki.org/wiki/Well_Chemicals_Data_Sources | accessdate = 2015-08-10 }}</ref> | ||
+ | == References == | ||
__NOEDITSECTION__ | __NOEDITSECTION__ | ||
[[Category:Wells]] | [[Category:Wells]] |
Well ID: 42-439-36735 | Loading map...
{"type":"SATELLITE","minzoom":false,"maxzoom":false,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"mappingservice":"googlemaps3","width":"100%","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"wmsoverlay":false,"copycoords":false,"static":false,"zoom":14,"layers":[],"controls":["pan","zoom","type","scale","streetview","rotate"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"resizable":false,"kmlrezoom":false,"poi":true,"markercluster":false,"clustergridsize":60,"clustermaxzoom":20,"clusterzoomonclick":true,"clusteraveragecenter":true,"clusterminsize":2,"imageoverlays":[],"kml":[],"gkml":[],"searchmarkers":"","enablefullscreen":false,"scrollwheelzoom":false,"locations":[{"text":"","title":"","link":"","lat":32.7563057,"lon":-97.0713679,"icon":""}]} Map displayed above is an approximation of the well location based on well county. |
County: Tarrant | |
District: 09 | |
Well Type: Gas | |
Well Number: 2H | |
Lease Number: 269744 | |
Wellbore Shutin Date: | |
Well Shutin Date: | |
Subject to Rule 14(B)(2): No | |
14(B)(2) Status: Not subject for extension | |
Location: Land |
For data sources see[1]
Year | Month | Oil Volume (BBL) | Gas Volume (MCF) | Condensate Volume (BBL) | Casing Head Gas Volume (MCF) | Lease Name | Operator Name | Field Name |
---|---|---|---|---|---|---|---|---|
2013 | 03 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2013 | 04 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2013 | 05 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2013 | 06 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2013 | 07 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2013 | 08 | 0 | 46196 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2013 | 09 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2013 | 10 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2013 | 11 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2013 | 12 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2014 | 01 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2014 | 02 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2014 | 03 | 0 | 76 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2014 | 04 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2014 | 05 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2014 | 06 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2014 | 07 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2014 | 08 | 0 | 36265 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2014 | 09 | 0 | 84162 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2014 | 10 | 0 | 71436 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, INC. | NEWARK, EAST (BARNETT SHALE) |
2014 | 11 | 0 | 68363 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, L.L.C. | NEWARK, EAST (BARNETT SHALE) |
2014 | 12 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, L.L.C. | NEWARK, EAST (BARNETT SHALE) |
2015 | 01 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, L.L.C. | NEWARK, EAST (BARNETT SHALE) |
2015 | 02 | 0 | 0 | 0 | 0 | HOME RUN | CHESAPEAKE OPERATING, L.L.C. | NEWARK, EAST (BARNETT SHALE) |
For data sources see[2]
HF Fluid Concentration | Ingredient | Additive Concentration | Trade Name | Purpose | CAS number | Supplier |
---|---|---|---|---|---|---|
0.00375 | Glutaraldehyde (Pentanediol) | 15.0 | ALPHA 114 | Anti-Bacterial Agent | 000111-30-8 | BAKER HUGHES |
0.00125 | Dimethyl benzyl ammonium chloride | 5.0 | ALPHA 114 | Anti-Bacterial Agent | 000139-08-2 | BAKER HUGHES |
0.6939 | Water | 85.0 | 15 hcl | Acid | 007732-18-5 | TRICAN |
0.12245 | Hydrochloric Acid | 15.0 | 15 hcl | Acid | 007647-01-0 | TRICAN |
0.00089 | Proprietary Cured Acrylic Resin (EnCap HP) | 25.0 | EnCap HP | Breaker | TRADE SECRET | TRICAN |
0.00213 | Ammonium Persulfate | 60.0 | EnCap HP | Breaker | 007727-54-0 | TRICAN |
88.2022 | Water | 100.0 | Fresh Water | Carrier/Base Fluid | 007732-18-5 | CHESAPEAKE ENERGY |
0.00097 | Diethylene Glycol | 5.0 | SCALETROL 7208 | Scale Inhibitor | 000111-46-6 | BAKER HUGHES |
0.00485 | Ethylene Glycol | 25.0 | SCALETROL 7208 | Scale Inhibitor | 000107-21-1 | BAKER HUGHES |
0.08645 | Petroleum Distillate Hydrotreated Light | 60.0 | WG-111L | Gelling Agent | 064742-47-8 | TRICAN |
0.08645 | Polysaccharide blend | 60.0 | WG-111L | Gelling Agent | NA | TRICAN |
0.02798 | Methanol (Methyl Alcohol) | 0.0 | ALPHA 114 | BAKER HUGHES | 000067-56-1 | SCALETROL 7208 |
0.02173 | Sodium Chloride | 0.0 | ALPHA 114 | BAKER HUGHES | 007647-14-5 | SCALETROL 7208 |
0.02173 | Proprietary Polyacrylate | 0.0 | ALPHA 114 | BAKER HUGHES | TRADE SECRET | SCALETROL 7208 |
0.04971 | Water | 0.0 | ALPHA 114 | BAKER HUGHES | 007732-18-5 | SCALETROL 7208 |
71050.0 | 2-Propenoic | 0.0 | ALPHA 114 | BAKER HUGHES | Polymer with Sodium | SCALETROL 7208 |
0.02173 | Potassium Chloride | 0.0 | ALPHA 114 | BAKER HUGHES | 007447-40-7 | SCALETROL 7208 |
0.02798 | Ethanol | 0.0 | ALPHA 114 | BAKER HUGHES | 000064-17-5 | SCALETROL 7208 |
7e-05 | Methanol (Methyl Alcohol) | 40.0 | LAI-20 | Corrosion Inhibitor | 000067-56-1 | TRICAN |
1e-05 | Propargyl Alcohol (2-Propynol) | 8.0 | LAI-20 | Corrosion Inhibitor | 000107-19-7 | TRICAN |
0.06456 | Propylene Carbonate | 0.0 | FEA-20 | LCL-21LTB | 000108-32-7 | LAI-20 |
0.00012 | Proprietary Alcohol Ethoxylate Surfactants | 0.0 | FEA-20 | LCL-21LTB | TRADE SECRET | LAI-20 |
0.06456 | Guar Gum | 0.0 | FEA-20 | LCL-21LTB | 009000-30-0 | LAI-20 |
0.00012 | Modified Thiourea Polymer | 0.0 | FEA-20 | LCL-21LTB | 068527-49-1 | LAI-20 |
0.00012 | Proprietary n-Olefin | 0.0 | FEA-20 | LCL-21LTB | TRADE SECRET | LAI-20 |
0.02964 | Water | 0.0 | FEA-20 | LCL-21LTB | 007732-18-5 | LAI-20 |
0.06456 | Sorbitan Trioleate | 0.0 | FEA-20 | LCL-21LTB | 026266-58-0 | LAI-20 |
0.06456 | Modified Bentonite (Organophillic Clay) | 0.0 | FEA-20 | LCL-21LTB | 068953-58-2 | LAI-20 |
0.00015 | Proprietary Alcohol Alkoxylate | 20.0 | S-15 (Surfactant) | Surfactant | TRADE SECRET | TRICAN |
0.00015 | Methanol (Methyl Alcohol) | 20.0 | S-15 (Surfactant) | Surfactant | 000067-56-1 | TRICAN |
0.00174 | Potassium Hydroxide | 5.0 | LCL-21LTB | Cross Linker | 001310-58-3 | TRICAN |
0.01046 | Potassium Metaborate | 30.0 | LCL-21LTB | Cross Linker | 016481-66-6 | TRICAN |
0.00349 | Ethylene Glycol | 10.0 | LCL-21LTB | Cross Linker | 000107-21-1 | TRICAN |
0.01599 | Petroleum Distillate Hydrotreated Light | 60.0 | FR-12 (Anionic Acrylamide) | Friction Reducer | 064742-47-8 | TRICAN |
0.00053 | Quaternary Ammonium Chloride (Ammonium Chloride) | 2.0 | FR-12 (Anionic Acrylamide) | Friction Reducer | 012125-02-9 | TRICAN |
0.00068 | Acetic acid | 85.0 | FEA-20 | Iron Control Agent | 000064-19-7 | TRICAN |
4e-05 | Methanol (Methyl Alcohol) | 5.0 | FEA-20 | Iron Control Agent | 000067-56-1 | TRICAN |
0.00111 | Ammonium Persulfate | 100.0 | WBO-1 (Oxidizer Breaker) | Breaker | 007727-54-0 | TRICAN |
For data sources see[3]