This repo contains code for modelling the coupled surface and volume growth of shells in a finite strain kinematical framework. The corresponding paper is arXiv:1901.00497 [q-bio.QM]. S. Rudraraju, D.E. Moulton, R. Chirat, A. Goriely and K. Garikipati, "A computational framework for the morpho-elastic development of molluskan shells by surface and volume growth". Please consider citing the above paper, if you use this repo.