Document signing

Answer
There is no rule for that. With the signature you want to evidence that someone with authority approved the document. That someone has a position. For example, Mary approves document A not because she is Mary but because she occupies the Quality Manager position. Adding the printed name is a possibility but sometimes occupies much needed space.

The following material will provide you information about documents:
- Article – List of mandatory documents required by ISO 9001:2015 - https://advisera.com/9001academy/knowledgebase/list-of-mandatory-documents-required-by-iso-90012015/
- - Free course – ISO 9001:2015 Internal Auditor Course - https://advisera.com/training/iso-9001-internal-auditor-course/
- Book - Managing ISO Documentation: A Plain English Guide - https://advisera.com/books/managing-iso-documentation-plain-english-guide/