Flight -- from Eric Weisstein's World of Physics

Anderson, J. D. Introduction to Flight, 3rd ed. New York: McGraw-Hill, 1989.

Corless, R. M.; Gonnet, G. H.; Hare, D. E. G.; Jeffrey, D. J.; and Knuth, D. E. "On the Lambert W Function." Adv. Comput. Math. 5, 329-359, 1996.