Where do we know Shraga's birth date from?
From a record on JewishGen it looks like it was 1888.
I can´t recall exactly but if i was as specific with the details i put, e.g profession and d.o.b i believ i git it from a yad vashem record. I will check exactly when i get home. some of the records however i got from the following page: http://www.museumoffamilyhistory.com/z/cem-zambrow-matzevot.htm