Precious historical treasures might be hidden between the lines of a text. There are many implicit details which can be extracted from a text, particularly if one has access to an entire corpus of texts pertaining to the given subject. One of these details is the identification of the era in which the author of the given document(s) lived. For rabbinic documents written in Hebrew and Aramaic, which are almost without exception undated and do not contain any bibliographic section, this problem is extremely important. The aim of this novel research is to find in which years an author was born and died, based on his documents and the documents of other authors (whose birth and death years are known) who refer to the author under discussion or are mentioned by him. Such estimates can help determine the time frame in which certain documents were written and in some cases identify an anonymous author. In the framework of this research, we formulate various kinds of "iron-clad", heuristic and greedy constraints defining the birth and death years of an author based on citations referring to him or mentioned by him. Experiments applied on a corpus containing texts composed by rabbinic authors show reasonable results.