RT Journal Article SR Electronic T1 Correct use of aerosol inhalers JF Canadian Medical Association Journal JO CMAJ FD Canadian Medical Association SP 21a OP 22 VO 117 IS 1 A1 Tuttle, C. B. A1 Sidorov, J. YR 1977 UL http://www.cmaj.ca/content/117/1/21a.abstract