1. Alomari, M.W.: On the Davis–Wielandt radius inequalities of Hilbert space operators. (2020). arXiv:2008.00758 [math.FA]
2. Bag, S., Bhunia, P., Paul, K.: Bounds of numerical radius of bounded linear operator using $$t$$-Aluthge transform. Math. Inequal. Appl. 23(3), 991–1004 (2020)
3. Bhunia, P., Sain, D., Paul, K.: On the Davis-Wielandt shell of an operator and the Davis–Wielandt index of a normed linear space. (2020). arXiv:2006.15323 [math.FA]
4. Bhunia, P., Bhanja, A., Bag, S., Paul, K.: Bounds for the Davis–Wielandt radius of bounded linear operators. Ann. Funct. Anal. 12, 18 (2021). https://doi.org/10.1007/s43034-020-00102-9
5. Buzano, M.L. Generalizzatione della diseguaglianza di Cauchy–Schwarz. Rend. Sem. Mat. Univ. e Politech. Trimo 31 (1971/73) 405–409