halacha - Can a woman who did not receive a get but only a civil divorce marry again?

Scenarios

1. 
   

   Where is there a discussion where a woman (married in a religious ceremony) who did not receive a get but only a civil divorce can marry again?

   
   


2. 
   

   If she and her husband did not marry in a religious ceremony, but only in a civil ceremony, does she still need a get, before she can remarry?