I am not sure if i can help, but there is an Appendix: Regular Expressions in Identity Awareness Administration Guide R77 Versions p.105f. Further information can be found in sk63764 "Error while trying to find LSS for pattern. Verify that pattern contains LSS" message in SmartDashb... Here we find that that for IA and DLP The filtering is case-insensitive.
For study material you have Regular Expressions on Curlie. But RegEx has no easy syntax at all - as we read in wikipedia: The specific syntax rules vary depending on the specific implementation, programming language, or library in use. Additionally, the functionality of regex implementations can vary between versions.
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