BESSEL an OLBERS, 1821 April 9
Nachtraege zur Physik, Chronologie und Astronomie Bd.11, Abt.1, GDML_Books, (1927), p. 332 / Harvested from
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@article{PPN236020595+dmdlog251,
     title = {BESSEL an OLBERS, 1821 April 9},
     booktitle = {Nachtraege zur Physik, Chronologie und Astronomie Bd.11, Abt.1},
     series = {GDML\_Books},
     year = {1927},
     pages = {332},
     url = {http://dml.mathdoc.fr/item/PPN236020595+dmdlog251}
}

 (éd.). BESSEL an OLBERS, 1821 April 9, dans Nachtraege zur Physik, Chronologie und Astronomie Bd.11, Abt.1, GDML_Books,  (1927), p. 332. http://gdmltest.u-ga.fr/item/PPN236020595+dmdlog251/