Single-dose versus 3-day cotrimoxazole prophylaxis in transurethral resection or greenlight laser vaporisation of the prostate: study protocol for a multicentre randomised placebo... by Speich, B, Bausch, K, Roth, JA, Hemkens, LG, Ewald, H, Vogt, DR, Bruni, N, Deuster, S, Seifert, H-H, Widmer, AF