Appendix De Calculo Variationum.
In Quo Methodus Inveniendi Functiones Duarum et Plurium Variabilium, ex Data Relatione Differentialium Cuiusvis Gradus Pertractatur Volumen 3, GDML_Books, (1793), p. 379 / Harvested from
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@article{PPN597788405+DMDLOG_0007,
     title = {Appendix De Calculo Variationum.},
     booktitle = {In Quo Methodus Inveniendi Functiones Duarum et Plurium Variabilium, ex Data Relatione Differentialium Cuiusvis Gradus Pertractatur Volumen 3},
     series = {GDML\_Books},
     publisher = {Academia Imperialis Scientiarum},
     address = {Petropoli},
     year = {1793},
     pages = {379},
     url = {http://dml.mathdoc.fr/item/PPN597788405+DMDLOG_0007}
}

 (éd.). Appendix De Calculo Variationum., dans In Quo Methodus Inveniendi Functiones Duarum et Plurium Variabilium, ex Data Relatione Differentialium Cuiusvis Gradus Pertractatur Volumen 3, GDML_Books,  (1793), p. 379. http://gdmltest.u-ga.fr/item/PPN597788405+DMDLOG_0007/