Παραπομπή APA
European Commission. (1998). Quattro: Quality approach in tendering urban public transport operations. Luxembourg: Office for Official Publications of the European Communities.
Παραπομπή Chicago StyleEuropean Commission. Quattro: Quality Approach in Tendering Urban Public Transport Operations. Luxembourg: Office for Official Publications of the European Communities, 1998.
Παραπομπή MLAEuropean Commission. Quattro: Quality Approach in Tendering Urban Public Transport Operations. Luxembourg: Office for Official Publications of the European Communities, 1998.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.