There are a number of applications of source-criticsm in the Tanakh, including:
- Named sources of judges, samuel, kings, etc.
- The documentary-hypothesis
- Subdivisions of isaiah
- Material used by the compiler of ezra-nehemiah
In New Testament studies, the synoptic-problem is the primary application of source-criticsm, though scholars have also proposed portions of other texts come from older sources.
For more information, see the Wikipedia article: Source criticism (biblical studies)