Barber, Jerry. "Intermolecular forces in the critical azeotropic system propane-perfluorocyclobutane : description of forces in the vapor region via virial coefficients and in the liquid region via internal pressure and internal force /." Doctoral dissertation, Ohio State University, 1968. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486646068586998Chicago Manual of Style (17th edition)