References
- Linear Algebra and Appl. v.76 An extremal property of the permanent and the determinant R.B.Bapat;V.s.Sunder
- Amer.Math.Monthly v.89 Is there a permanental analog to Oppenheim's inequality J.Chollet
- Linear Algebra and Appl. v.94 A note on the analog to Oppenheim's inequality R.J.Gregorac;I.R.Hensel
- Linear and Multilinear Algebra v.212 no.213 Notes on Hadamard products of matrices F.-Z.Zhang