The mission of Cyril and Methodius to Moravia

• Life of Constantine
• Petkov 48-54
  
• Henrik Birnbaum, "The Lives of Sts. Constantine-Cyril and Methodius viewed against the background of Byzantine and early Slavic hagiography," in To Hellenikon. Studies in Honor of Speros Vryonis, Jr., ed. by Jelisaveta Stanojevich Allen, Christos P. Ioannides, John S. Langdon, and Stephen W. Reinert, vol. 2 (New Rochelle, 1993), pp. 3-23 (Pack)
• see a brief presentation, a facsimile (sample copy), and an acoustic reconstruction of the Freising Manuscripts
• see an introduction to the Glagolitic script

Prince Boris and the conversion of Bulgaria

• Curta 166-179
• Rosina Kostova, "St. Kliment of Ohrid and his monastery: some more archaeology of the written evidence," in Vizantiia, Balkanite, Evropa. Izsledvaniia v chest an Prof. Vasilka Tăpkova-Zaimova (Sofia, 2006), pp. 593-605 (Pack)
• Petkov 24-31 (or see the complete text of the Responsa of Pope Nicholas I), 33 (no. 34) and 36 (no. 43), 41 (no. 63), 54-60,  93-107, 143-163
  
• see a brief biography of Prince Boris of Bulgaria
• see an icon of St. Clement of Ohrid (now in the St. Mary Most Glorious Church in Ohrid)
• visit St. Clement's monastery "St. Panteleimon" and the monastery of St. Naum in Ohrid