@Book{BVMC:620193,
author = {Valerius, Cornelius},
title = {Cornelij Velerij Ultraiectini Grammaticarum institutionum liber [primus-quatuor]},
url = {http://www.cervantesvirtual.com/obra/cornelij-velerij-ultraiectini-grammaticarum-institutionum-liber-primus-quatuor-1}
}