Ms. Olczak-Ronikier 's grandmother , Janina Mortkowicz , was the wife of Ms. Olczak-Ronikier 's hero , her grandfather Jakub Mortkowicz , who opened what became one of Warsaw 's most important bookstores and publishing houses at the end of World War I . '' He was an example of the tragic love of assimilated Jews in Poland , '' Ms. Olczak-Ronikier said . ''