 Sikorski was a member of the editorial staff at "Komunikaty Mazursko-Warmińskie", and also a member of staff at "Frombork's Commentaries" ("Komentarze Fromborskie"), and also the substitute editor-in-chief of "Olsztyn Yearly" (""),

Jerzy Sikorski published a number of short biographies of Warmian Chapter canons and members in the "Polish Biographical Dictionary", which is printed by the Polish Academy of Sciences.These included biographies of Preuck Jan (1575–1631), Preuck Jerzy (d. 1556), Reich Feliks (c. 1475–1539), Sculteti Aleksander (1485–1564), Sculteti Bernard (d. 1518), and Sculteti Jan (d. 1526).Reviewing the document "Locationes mansorum desertorum" ("Allocation of abandoned fiefs"), which was written by Copernicus in the region of Olsztyn Castle, Olsztyn, Poland, Jerzy Sikorski discovered that, out of the 136 names of allocation of fiefs, 60 were Polish names (peasants had only first names) written in phonetically correct Polish.