[1]
C. V. Calamari, “Evaluation of two methods for early pregnancy diagnosis in ewes: transrectal ultrasonography and pregnancy detector for small ruminant (DPPR-80®)”, Braz. J. Vet. Res. Anim. Sci., vol. 40, no. 4, pp. 261–266, Jan. 2003, doi: 10.1590/S1413-95962003000400004.