check these links for study i hope it will helpful for you

http://www.organic-chemistry.org/nam...zeff-rule.shtm

http://www.organic-chemistry.org/nam...mann-rule.shtm

https://www.physicsforums.com/thread...s-rule.798108/
i sear many vedio links for these rules but all links are present on YouTube.com which we cannot open in Pakistan.

in addition i also paste my personal notes on these topics but letter.