PHAM, Trong Hoa. An Approach to Determine the Stable Operating Area for Internal Gear Motors and Pumps Based on Safe Lubrication Oil Film Thickness. Old Journal, [S. l.], n. 138B, p. 38–44, 2019. Disponível em: https://jst.vn/index.php/old/article/view/593. Acesso em: 2 aug. 2025.