Matching up torn pages on Shabbos

Hi,

If a page in a book is torn, one may align the two parts on Shabbos in reading the book; this is not called writing, and separating the parts is not called erasing.

However, one may not align the two parts if there is a particular letter which is split, and which would not be readable without aligning the parts.

(Rav Moshe Feinstein, Igrot Moshe Yoreh Deah 2:75)

פתקא טבא,
Mordechai