The most concise and useful resource I found was from when Ubuntu moved to dash for /bin/sh:
https://wiki.ubuntu.com/DashAsBinSh
It covered pretty much every issue I had in a relatively large shell script (about 3200 lines including library code).
https://wiki.ubuntu.com/DashAsBinSh
It covered pretty much every issue I had in a relatively large shell script (about 3200 lines including library code).