V. Kompiš and L. Fraštia, “Polynomial representation of hybrid finite elements”, Comp. Assist. Methods Eng. Sci., vol. 4, no. 3-4, pp. 521–532, Dec. 1997, Accessed: Mar. 05, 2026. [Online]. Available: https://cames.ippt.gov.pl/index.php/cames/article/view/1387