Respect for Deeni Literature

Disposing of something with the name of Allah Ta'ala

Q: 

1. Is it permissible to dispose of something with the name of Allah Ta'ala written inside of it, if the writing is covered? 

For example, a copy has random pages where the name of Allah Ta'ala is written, but these writings are covered by other pages and covers of the copy. 

2. If not, then is one required to check every copy and mark over them so it cannot be seen? 

3. What other writings does one have to cut off (or just cover) before disposing?