A Guide for Digitally Signing PDF Files in C#, by Andrew Wilson
NET PDF Signature Library (Developer Tutorial)
Java implementation of Digital Signatures in Cryptography - GeeksforGeeks
How to Sign PDF with a Digital Signature
View digital signature and certificate details - Microsoft Support
Verifying installer signatures
How to Sign PDF with Digital Signature Certificate (in Adobe Acrobat Reader)
Digital Signature Standard (DSS) - GeeksforGeeks
Digitally Sign and Verify Signatures in PDF Files Using C#: A Complete Guide
Solutions for PDF electronic digital signature integration - iText
How to Digitally Sign PDF Documents: 3 Ways