Best way to reference another class library

Tried it out, seems to work fine!

For future refence:

Accessing the methods of the referenced class instance in the example by PaulS has to be done with "->" not "."

int read = _pCent->digitalRead(_pin);

instead of

int read = _pCent.digitalRead(_pin);

Don't ask me why, yet, maybe later when I've gotten a bit more into c/c++