Michels KB, Rothman KJ. Update on unethical use of placebos in randomised trials. Bioethics. 2003 Apr;17(2):188-204.
Nicholls TJ, Green KL, Cook DJ, Rogers DJ, Wolowacz SE, Smart JD. An investigation of lectins for use in ophthalmic drug delivery. Int J Pharm. 1996;138(2):175-83.