Glass wool column filtration of human semen: relation to swim up procedure and outcome of IVF - van der Hen,H.H.; Jeyendran,R.S.; Al-Hasani,S.; Tunnerhoff,A.; Hoebbel,K.; Diedrich,K.; Krebs,D.; Perez-Pelaez,M. (Hum Reprod, 1988)