Hornberger , K., C. C. Lyman, J. M. Baldrighi, and G.R. Holyoak. “Plasma Altrenogest Concentrations in Mares After Intrarectal or Intravaginal Administration”. Clinical Theriogenology 11, no. 1 (March 1, 2019): 59-65. Accessed April 1, 2026. https://clinicaltheriogenology.net/index.php/CT/article/view/11190.