Stoops, W., Lile, J., Fillmore, M., Glaser, P., & Rush, C. (2005). Reinforcing effects of modafinil: influence of dose and behavioral demands following drug administration. Psychopharmacology, 182(1), 186-93. https://doi.org/10.1007/s00213-005-0044-1

Stoops, W., Glaser, P., Fillmore, M., & Rush, C. (2004). Reinforcing, subject-rated, performance and physiological effects of methylphenidate and d-amphetamine in stimulant abusing humans. Journal of Psychopharmacology (Oxford, England), 18(4), 534-43. https://doi.org/10.1177/0269881104047281