Popova, I. (2006). Enea Silvio Pikolomini (Papa Pij II) i balkanite prez XV v: (istoričeski etjudi) = Aeneas Sylvius Piccolomini (Pope Pius II) and the Balkans in the 15th century. Faber.
Chicago-Zitierstil (17. Ausg.)Popova, Ivajla. Enea Silvio Pikolomini (Papa Pij II) I Balkanite Prez XV V: (istoričeski Etjudi) = Aeneas Sylvius Piccolomini (Pope Pius II) and the Balkans in the 15th Century. V. Tărnovo: Faber, 2006.
MLA-Zitierstil (9. Ausg.)Popova, Ivajla. Enea Silvio Pikolomini (Papa Pij II) I Balkanite Prez XV V: (istoričeski Etjudi) = Aeneas Sylvius Piccolomini (Pope Pius II) and the Balkans in the 15th Century. Faber, 2006.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.