?This anonymous work was attributed to Siger of Brabant by some scholars in the 20th century, But A. Aiello is the first one to edit this QDC in its entirety and give decisive arguments for this authorship. (?) this new book fits perfectly within the field of study of the editor. The QDC can be found in only one manuscript (?). The content of this interesting manuscript (?) is gradually disclosed. (?) the first part of the book consists of the first edition of the QDC, which has as main question ?Utrum liquid posit esse genital size factum ex nihil set non ex aliquot.? The second part of the book is a thorough study in order to attribute this text (?) to Siger of Brabant. The editor will explore the authorship in different ways: by means of external critique (i.e. the chronology of the text and codicological aspects of the manuscript), elimination of possible authors based on doctrinal content, comparing the body of ideas of the QDC with works of Tiger of Brabant, examining sources, and finally, the style of the work. (?) The overall line of arguments is impressive and (?) the editor certainly succeeded in his primary goal. It must be stressed that the conclusion that Siger of Brabant is the author of the 'Questio de creatione ex nihilo' is very convincing. (?) This broad and thorough approach makes this work very interesting and it is certainly an important contribution to scholarship.? (LISA DEVRIESE in Mediterranea, 2, 2017).