Prevention of symptomatic thrombosis with short term (low molecular weight) heparin in patients wirth rheumatoid arthritis after hip or knee replacement. - van Heereveld,H.A.; Laan,R.F.; van den Hoogen,F.H.; Malefijt,M.C.; Novakova,I.R.; van de Putte,L.B. (Ann Rheum Dis, 2001)