Endometriosis classification systems: an international survey to map current knowledge and uptake - Zondervan, Krina T; Missmer, Stacey; Abrão, Maurício Simões; Einarsson, Jon I.; Horne, Andrew W; Johnson, Neil P; Lee, Ted T. M; Petrozza, John; Tomassetti, Carla; Vermeulen, Nathalie (Journal of minimally invasive gynecology, 2022)