@article{arxiv.physics/9909061,
title = {On some functional transformations relative to linear PDEs of second order},
author = {Jean Delsarte},
journal= {arXiv preprint arXiv:physics/9909061},
year = {2007}
}
Comments
13 pages, LaTex, forward and translations by H.C. Rosu who is indebted to J. Beckers for kindly sending copy of the work, idioms: original French, English, Romanian, Spanish