Mathew, Agnus, et al. “Efficacy of Cytobrush, Uterine Lavage and Endometrial Biopsy Techniques for Cytological and Cultural Evaluation of Endometritis in Barren Mares”. International Journal of Livestock Research, vol. 10, no. 9, Sept. 2020, pp. 113-2, doi:10.5455/ijlr.20200430095419 .