PAPANIKOS, Gregory T. in PAPPAS, Nicholas (ur.), 2010, Horizons in education [na spletu]. Strokovna monografija. Athens : Athens institute for education and research, ATINER. [Dostopano 20 april 2025]. ISBN 978-960-6672-88-0. Pridobljeno s: http://www.pef.uni-lj.si/fileadmin/Datoteke/Knjiznica/Datoteke/HorizonsInEducation.pdf