In 1942, Leibowitz began mailing out stencils of questions on the weekly Torah reading to anyone who requested them.
These worksheets, which she called gilyonot (pages) would be sent back to her, and she would personally review them and return them with corrections and comments.
They became very popular and in demand by people from all sectors of Israeli society.
In 1954, Leibowitz began publishing her "Studies", which included many of the questions that appeared on her study sheets, along with selected traditional commentaries and her own notes on them.
Over time, these studies were collected into five books, one for each book of the Torah.
The five books were subsequently translated to English by Rabbi Dr Aryeh (Laibel/Leonard) Newman.