OLBERS an BESSEL, 1820 April 20
Nachtraege zur Physik, Chronologie und Astronomie Bd.11, Abt.1, GDML_Books, (1927), p. 319 / Harvested from
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@article{PPN236020595+dmdlog240,
     title = {OLBERS an BESSEL, 1820 April 20},
     booktitle = {Nachtraege zur Physik, Chronologie und Astronomie Bd.11, Abt.1},
     series = {GDML\_Books},
     year = {1927},
     pages = {319},
     url = {http://dml.mathdoc.fr/item/PPN236020595+dmdlog240}
}

 (éd.). OLBERS an BESSEL, 1820 April 20, dans Nachtraege zur Physik, Chronologie und Astronomie Bd.11, Abt.1, GDML_Books,  (1927), p. 319. http://gdmltest.u-ga.fr/item/PPN236020595+dmdlog240/