1. Endometrial wavelike activity, endometrial thickness, and ultrasound texture in controlled ovarian hyperstimulation cycles 
Marga M IJland, M.D., Johannes L.H Evers, M.D., Gerard A.J Dunselman, M.D., Henk J Hoogland, M.D. 
Fertility and Sterility 
Volume 70, Issue 2, Pages (August 1998)
DOI: /S (98)

2. FIGURE 1
Relative distribution of wave type patterns throughout controlled ovarian hyperstimulation cycles. ■ = opposing waves; = waves from cervix to fundus; = waves from fundus to cervix; = random activity; □ = no activity.
Fertility and Sterility  , DOI: ( /S (98) )