World endometriosis society consensus on the classification of endometriosis - Johnson, N P; Hummelshoj, L; Adamson, G D; Keckstien, J; Taylor, H S; Abrao, M S; Bush, D; Kiesel, L; Tamimi, R; Scharpe-Timms, K L; Rombauts, L; Giudice, L C (Hum Reprod, 2017)