Hello, I apologize that I use English here, but I cannot speak German. I would like to correct the date and place of birth of Johann Hamza (Jan Hamža).
My source is this: https://en.isabart.org/person/52689
Citing from there: Datum narození viz. sdělení Zdeňka Geista Polaně Bregantové, údaje pocházejí "z knihy narozených z Kostelní Myslové s datem 21. června 1848 a rovněž rozhodnutí o udělení domovského práva ve Vídni pro Johanna Hamzu a jeho rodinu, které obsahuje správné datum a místo narození. Tento údaj potvrzuje i záznam z vídeňského centrálního hřbitova, kde byl Johann Hamza pohřben."
Translation: Date of birth see communication from Zdeněk Geist to Polana Bregantová, the data come "from the book of births from Kostelní Myslová dated June 21, 1848, as well as the decision to grant Heimatrecht in Vienna to Johann Hamza and his family, which contains the correct date and place of birth. This data is also confirmed by the record from the Vienna Central Cemetery where Johann Hamza was buried."
Let me add that Zdeněk Geist is a Czech art historian and collector; art from his collection was used in exhibition "Contemporaries of Mahler" that contained Hamsa's paintings in Jihlava in 2014.
Kostelní Myslová is 5 km to the south from Teltsch/Telč.
Johann Hamza spent his childhood and youth in the city of Teltsch. (Could someone please add that to the page?)
The date of death and even exact position of Hamsa's grave in the Wien Central Cemetery cen be found here: https://www.friedhoefewien.at/verstorbenensuche-detail?fname=Johann+Hamza&id=04%3E5R9HG26&initialId=04%3E5R9HG26&fdate=1927-12-27&c=046&hist=true#! But I don't know how to add this link to the page; help would be welcome.