Some persons have strange images (dbo:thumbnail)
https://data.swissbib.ch/person/99ec6414-7f37-3462-8f19-07889a5d5165 https://data.swissbib.ch/person/68d6b9f3-3368-3d1f-a81c-ff0c527035b2 https://data.swissbib.ch/person/04b82d30-a254-3028-85c7-8b31ef56eaba
However in wikidata the P18 is fine : https://www.wikidata.org/wiki/Q3052772 https://www.wikidata.org/wiki/Q989 https://www.wikidata.org/wiki/Q3910
@SoulLink : a problem in the import script ?