Loaning as a Mitzvah

Is there a mitzvah to loan money?  Many of us would think that the answer is “no” – it’s not real tzedakah, because the person has to give the money back in the end.  What is obvious to us is that there is a mitzvah of tzedakah – giving money to a person in need.  Surprisingly, however, this mitzvah appears nowhere in the Torah.  Look at the following verses that talk about supporting a poor person through financial assistance {source ‎1-‎‎3}.