Medjadj, A., H. Elhendi, and L. Belarbi. “Some Biharmonic Problems on the Tangent Bundle With a Berger-Type Deformed Sasaki Metric”. The Journal of the Indian Mathematical Society, vol. 88, no. 3-4, June 2021, pp. 217–236, doi:10.18311/jims/2021/26439.