“The Relationship Between G1 (c.260 G>A) and G4 (c.721 G>A) Polymorphisms in the GDF9 Gene and the Litter Size of Sheep: A Meta-Analysis Study”. 2023. Journal of Advanced Veterinary and Animal Research 10 (4): 599-607. https://www.banglajol.info/index.php/JAVAR/article/view/80731.