01-18269 [Institute of Educational Policy: 18269]
Gr. Xenopoulos, Ar. P. Kourtidis, G. Konidaris, O Pirgos tou Vosporou ke alla diigimata. Anagnostiko E΄ Dimotikou, ed. , Ioannis D. Kollaros, Athina 1929, Institute of Educational Policy

05-00102 [University of Ioannina: 102]
Gr. Xenopoulos, Ar. P. Kourtidis, G. Konidaris, O pirgos tou Vosporou ke alla diigimata. Anagnostiko E΄ Dimotikou, ed. , Ioannis D. Kollaros, Vivliopolio tis "Estias", Athina 1931, University of Ioannina

20-01652 [Society for the Study of Modern Greek Culture and Education: 1652]
Gr. Xenopoulos, Ar. P. Kourtidis, G. Konidaris, O Pirgos tou Vosporou. Anagnostiko E΄ Dimotikou, ed. , Ioannis D. Kollaros, Vivliopolio tis "Estias", Athina 1928, Society for the Study of Modern Greek Culture and Education