What needs to be clarified
The analysis could distinguish verbatim reproduction, structural reworking and use of common material. Textual borrowing and independent authorship are separate questions.
Materials to prepare
- Complete versions of both publications, with dates and file or webpage provenance.
- The suspected common source in the version available during the relevant period.
- Available drafts, revision history, citation information and records of editing or joint preparation.
What to compare
- Which matches remain after identifying quotations, fixed phrases and required names.
- Whether unusual argument sequences, transitions, errors and examples recur.
- Whether the common source explains the matches without assuming direct copying between publications.
Possible outcome of the analysis
A possible output is a passage comparison classifying correspondences and alternative sources of similarity. Any overlap figure would include its calculation method and exclusions.
Limits of the conclusions
Linguistic analysis does not automatically establish an infringement or the creation order of unavailable drafts. An earlier accessible copy does not prove authorship of the entire text.