TERRA is a finite element code originally developed by John Baumgardner at Los Alamos National Laboratory to solve mantle convection problems. Peter Bunger, Woo-Sun Yang, David Stegman, Chris Reese and others contributed to further development of TERRA.

Baumgardner, J. P., Three-dimensional treatment of convective flow in the earth's mantle, J. Stat. Phys., 39, 501-511, 1985.
Bunge H. P., and J. R. Baumgardner, Mantle convection modeling o parallel virtual computers, Computers in Physics, 9, 207-215, 1995.
Bunge H. P., M. A. Richards and J. R. Baumgardner, Effect of depth-dependent viscosity on the planform of mantle, Nature, 379, 436-438, 1996.
Reese C. C., V. S. Solomatov, J. R. Baumgardner and W. S. Yang, Stagnant lid convection in a spherical shell, Phys. Earth Planet. Inter., 116, 1-7, 1999.

Stegman D. R., A. M. Jellinek, S. A. Zatman, M. A. Richards, An early lunar core dynamo driven by thermochemical mantle convection, Nature, 421, 143-146, 2003.
Reese C. C. , V. S. Solomatov, J. R. Baumgardner, D. R. Stegman and A. V. Vezolainen, Magmatic evolution of imapct-induced Martian mantle plumes and the origin of Tharsis, J. Geophys. Res., 109, 10.1029/2003JE002222, 2004.