1. Basic concepts
Foundations of the Theory of Groupoids and Groups, GDML_Books, (1974), p. [15]-21 / Harvested from
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@inbook{401540,
     title = {1. Basic concepts},
     booktitle = {Foundations of the Theory of Groupoids and Groups},
     series = {GDML\_Books},
     publisher = {VEB Deutscher Verlag der Wissenschaften},
     address = {Berlin},
     year = {1974},
     pages = {[15]-21},
     url = {http://dml.mathdoc.fr/item/401540}
}

 (éd.). 1. Basic concepts, dans Foundations of the Theory of Groupoids and Groups, GDML_Books,  (1974), pp. [15]-21. http://gdmltest.u-ga.fr/item/401540/