No idea.
Amazon has a few books:
https://www.amazon.com/Software-Engineering-Embedded-Systems-Integration-ebook/dp/B019ZU5APU/ref=sr_1_4?keywords=ISO26262&qid=1555694080&s=gateway&sr=8-4
Self assessment should go over what you need to know internally:
https://www.amazon.com/ISO-26262-Complete-Self-Assessment-Guide-ebook/dp/B07CVVGKCN/ref=sr_1_3?keywords=ISO26262&qid=1555694080&s=gateway&sr=8-3