Question

This sentence comes from two different sources: MLA Style

After the seppuku of the emperor’s son, Crown Prince Rudolf, in 1889, and his own father Archduke Charles Louis death from typhoid fever in 1896, Franz Ferdinand was groomed to inherit the throne ("Franz Ferdinand").

*So how do I cite both sources for that one sentece*

Answer 1

(Assuming you mean bibliography)
You should either:
+Pick one to cite.+
+Easy. Say: "(sentence) -from (first place) and (second place)"+
+If one was older than the other, say: "(sentence) -from (first place) following (second place)"+

I could be wrong. This is what I believe.

Answer 2

@TinyLittleHelper could I say this:

After the seppuku of the emperor’s son, Crown Prince Rudolf, in 1889, and his own father Archduke Charles Louis death from typhoid fever in 1896, Franz Ferdinand was groomed to inherit the throne ("Franz Ferdinand") and (Duffy, Michael).

Answer 3

Yes, that is okay to say. You don't have to write the hyphen that I wrote.
I hope that clears things up for you!