Prepositions with "le" or "les" titles

Question

What convention is usually used when the prepositions "à" or "de" are before the title of a book that begins with "le" or "les", for example "les miserables?"

Will it follow the same preposition structure? Like au, aux, du, des?

Accepted Answer

Is this a general question or related to a lesson here ?
An internet search turns up many answers. Examples below from a quick search : 
https://www.lawlessfrench.com/pronunciation/contractions-with-proper-nouns/
 
https://french.stackexchange.com/questions/29566/les-contractions-devant-le-titre-de-quelque-chose?noredirect=1&lq=1