XXXIII. Observationes circa bina biquadrata, quorum summam in duo alia biquadrata resolvere liceat.
Insunt plura inedita, tractatus de numerorum doctrina capita XVI aliaque Tomus prior, GDML_Books, (1849), p. 473 / Harvested from
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@article{PPN58477320X+DMDLOG_0042,
     title = {XXXIII. Observationes circa bina biquadrata, quorum summam in duo alia biquadrata resolvere liceat.},
     booktitle = {Insunt plura inedita, tractatus de numerorum doctrina capita XVI aliaque Tomus prior},
     series = {GDML\_Books},
     publisher = {Acad. Scient.},
     address = {Petropoli},
     year = {1849},
     pages = {473},
     url = {http://dml.mathdoc.fr/item/PPN58477320X+DMDLOG_0042}
}

 (éd.). XXXIII. Observationes circa bina biquadrata, quorum summam in duo alia biquadrata resolvere liceat., dans Insunt plura inedita, tractatus de numerorum doctrina capita XVI aliaque Tomus prior, GDML_Books,  (1849), p. 473. http://gdmltest.u-ga.fr/item/PPN58477320X+DMDLOG_0042/