In a 9 May 2018 post, Judith Singer asked about the given name
"Irsza" in Lithuanian.

A couple of additional resources for given names are:
Alexander Beider, A dictionary of Ashkenazic given names:
their origins, structure, pronunciation, and migrations
(Bergenfield, NJ: Avotaynu, Inc., 2001).
Alexander Beider, Handbook of Ashkenazic given names and their
variants (Bergenfield, NJ: Avotaynu, 2009).

The second book lists "Irsz (Hirsh)" on page 193 in a Google
Books search.

The Lithuanian Given Names Database on LitvakSIG.org lists
"Girsas" and "Hirsas" as local secular names for "Hirsh."

Deborra Wood
York SC, USA
Researching: BARRET, BITER/BYETER, HOCK, JACOBS, SCHINGLEDECKER

from Seduva?, Lithuania; South Africa

BLECHMAN >from Telsiai district, Lithuania
FRIEDLANDER >from Baisogala, Lithuania;
Seduva?, Lithuania; South Africa