The diminutive Zdenko is also sometimes a form of Sidonius.

Czech Republic

Latin

● 1291 Zdislaus (nom) RTT-1.1 III; 1295 Zdislaus (nom) ibid. V; 1316 Sdeslau (nom) ibid. X, Sdeslaus (nom) ibid. X; 1345 Sdislaum (acc) CDEM-7.2 629, Sdislaus (nom) ibid. 629, Sdizlai (gen) ibid. 629, Sdizlaus (nom) ibid. 629; 1349 Sdyslaus (nom) chlumecky 117; 1350 Zdyslaus (nom) ibid. 205; 1353 Sdyslaus (nom) ibid. 89; 1355 Sdyslaus (nom) ibid. 71; 1356 Sdislaus (nom) ibid. 150; 1360 Sdyslaum (acc) ibid. 475, p. 40

◑ 1295 Zdiko (nom) RTT-1.1 V; 1316 Sdenconem (acc) ibid. X, Sdenconis (gen) ibid. X, Sdenek (nom) ibid. X; 1343 Zdenko (nom) Rössler2 326, p. 149, Zdenkonem (acc) ibid. 326, p. 150, Zdenkonis (gen) ibid. 326, p. 149; 1351 Zdenco (nom) chlumecky 46, Zdencone (abl) ibid. 46; 1353 Sdenyck (nom) ibid. 41, p. 23, Sdenyek (nom) ibid. 41, p. 23; 1358 Sdichoni (dat) ibid. 219, p. 31