Joseph Sandel writes in his book "Umgekumene idishe kinstler":

"In another field there was produced Zigmunt Bolk, the long-time decorator of the Lemberg Grand Theatre and the costume-[proyektant] of this theatre.  Soon he had in the field collaborated with the theatre director of Yiddish theatre in Lemberg David Herman. For the theatre Bolk created decorations for the play "Itumim"(?) of influence and that the "father"(?) of Zigmunt Bolk also had participated. In the last years of the Second World War he had his son Henrial Bolk collaborated with him, who had manifested a significant artistic talent."

B. was killed by the Nazis.

Yosef Sandel -- "Umgekumene yidishe kinstler", Warsaw, 1957, Vol. II, p. 183.