Fraud Examination 5th Edition by Steve Albrecht,Chad Albrecht,Conan Albrecht, Mark Zimbelman

Exercise 38

ABC Company has instituted good internal controls and has never, until last month, had a problem with fraud. But, several weeks ago, someone with access to keys entered the controller's office and took two company checkbooks. Since then, several checks have been forged totaling $5,670. You are a certified fraud examiner and have been recruited to investigate the case.
1. Which theft act investigative method(s) should you use in this investigation