The first acknowledgment goes to OpenBabel developers, particularly to Geoffrey Hutchison, who merged in real time our changes and additions to the OpenBabel development trunk. Without OpenBabel, sdf2xyz2sdf would have probably never seen the light of day.

Next we wish to thank Prof. Jay Ponder for his kind and prompt feedback and for inspiring the development and the public release of sdf2xyz2sdf.

Thanks also to Nicolas Staelens for providing the first implementation of MMFF in TINKER.