[Předmluva]
Bernard Bolzano, GDML_Books, (1937), p. [3] / Harvested from
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@inbook{400089,
     title = {[P\v redmluva]},
     booktitle = {Bernard Bolzano},
     series = {GDML\_Books},
     publisher = {Pra\v zsk\'a odbo\v cka D\v elnick\'e akademie v Praze II., Hybernsk\'a ul. 7},
     address = {Praha},
     year = {1937},
     pages = {[3]-[3]},
     url = {http://dml.mathdoc.fr/item/400089}
}

 (éd.). [Předmluva], dans Bernard Bolzano, GDML_Books,  (1937), p. [3]. http://gdmltest.u-ga.fr/item/400089/