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 168 OP 169 VO 45 IS 4 A1 Letters, YR 1991 UL http://journal.pda.org/content/45/4/168.abstract AB