RT Journal Article SR Electronic T1 LETTERS TO THE EDITOR JF PDA Journal of Pharmaceutical Science and Technology JO PDA J Pharm Sci Technol FD Parenteral Drug Association (PDA) SP 2 OP 2 VO 43 IS 1 A1 Schwartz, R. T. YR 1989 UL http://journal.pda.org/content/43/1/2.abstract AB