1. Separation of motile human spermatozoa in assisted reproduction: evaluation of centrifugation and non-centrifugation-based techniques 
M Perloe, K.M Wittkowski, E.S Sills, M.J Tucker, G.D Palermo 
Fertility and Sterility 
Volume 73, Issue 4, Pages S13-S14 (April 2000)
DOI: /S (00)

2. Figure 1
Schematic of Zech dual-chamber capillary apparatus for separation of motile human spermatozoa. Migration of sperm placed in outer well (A) facilitates collection of a highly motile subpopulation in center chamber (B) without centrifugation.
Perloe. Human spermatozoa. Fertil Steril 2000.
Fertility and Sterility  , S13-S14DOI: ( /S (00) )