Superiority of a combined treatment of alendronate and alfacalcidol compared to the combination of alendronate and plain vitamin D or alfacalcidol alone in established postmenopausal or male osteoporosis (AAC-trial) - Ringe, JD; Farahmand, P; Schacht, E; Rozehnal, A (Rheumatol Int, 2007)