VSOP87 C Application Programming Interface (API)

On and off [albeit more off than on] over the past few years, I've been developing an astronomy C library. The crown jewel (in my opinion) is the VSOP87 portion of it since it solves the equations using the complete theory which is comprised of thousands of terms for each celestial body. A couple of days ago, I decided it was time to blow-off some of the dust and start working on it again. I did so by starting to write some documentation for the entire library using Doxygen, an open-source tool designed for such a task. If you're interested in seeing what I have done so far, point your browser at http://www.garychambers.com/orbital-docs/ and let me know what you think. I'm also trying to determine the license under which I should release the code, so I'd also appreciate any input you might have in that respect.