Somasundaran, Prof. P. Optimization of Surfactant Mixtures and Their Interfacial Behavior for Advanced Oil Recovery, report, March 4, 2002; (https://digital.library.unt.edu/ark:/67531/metadc742132/m1/1/: accessed October 21, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .