The life and the contribution of B. R. Sehgal, G. Yadigaroglu and G. Hewitt: remembrance statements

Solicited or voluntary statements have been collected by the Editor of the Special Issue (SI). Tributes to Sehgal, Yadigaroglu and Hewitt are reported in the alphabetical order of those who originated them. The concise tributes by N. Todreas related to all the three scientists constitute the paper PII-1 in this SI and are also reported hereafter. Romney Duffey and John Jones wrote dedicated tributes with scientific insights which constitute PII-7 and PII-8 in this SI. A number of others helped with biographies of Sehgal, Yadigaroglu and Hewitt and are acknowledged in paper PII-2