Use of beta-blocker therapy in older patients after acute myocardial infarction in Ontario.
Rochon PA, Anderson GM, Tu JV, Clark JP, Gurwitz JH, Szalai JP, Lau P. Use of beta-blocker therapy in older patients after acute myocardial infarction in Ontario. CMAJ. 1999 Nov 30; 161(11):1403-8.