What was the name of Bruno's mom and father?

I believe his mother's name is Elsa and his father's name is Ralf. These are the names in the movie version at least. I don't recall names in the book version. 

In the book 'The Boy in the Striped Pyjamas, main character, Bruno, has 2 nameless parents only refered to as either 'Mother' or 'Father' respectively. In the movie of the same name Bruno's Mother is named Elsa and his Father is Ralf.