1. R. M. Butler, Horizontal Holes for the Production of Oil, Gas, and Bitumens [Russian translation], NITs "Regulyarnaya i Khaoticheskaya Dinamika," Moscow–Izhevsk (2010).
2. R. M. Butler, Thermal Recovery of Oil and Bitumen, Prentice Hall, New Jersey (1991).
3. R. M. Butler and D. J. Stephens, The gravity drainage of steam-heated heavy oil to parallel horizontal wells, J. Can. Pet. Tech., 20, No. 6, 90–96 (1981).
4. J. Guo, C. Zan, D. S. Ma, and L. Shi, Oil production rate predictions for steam assisted gravity drainage based on highpressure experiments, Sci. China. Tech. Sci., 56, No. 2, 324–334 (2013).
5. L. Chow and R. M. Butler, Numerical simulation of the steam-assisted gravity drainage process (SAGD), J. Can. Pet. Tech., 35, No. 6, 55–62 (1996).