Petroman, C., I. Petroman, I. Bidireac, C.-L. Bejan, B. Bogosel, D. Marin, A. Lozici, and C. Chirila. “Studies on the Effect of the Number of Farrowed Sows in Heat Per Box”. Review on Agriculture and Rural Development, vol. 3, no. 1, Jan. 2014, pp. 156-9, https://analecta.hu/index.php/rard/article/view/13413.