When referencing PETSc in a publication please cite the following:
@Unpublished{petsc-home-page, Author = "Satish Balay and William D. Gropp and Lois Curfman McInnes and Barry F. Smith", Title = "{PETSc} home page", Note = <a href="http://www.mcs.anl.gov/petsc">"http://www.mcs.anl.gov/petsc", Year = "1998"}@TechReport{petsc-manual, Author = "Satish Balay and William D. Gropp and Lois Curfman McInnes and Barry F. Smith", Title = "{PETSc} 2.0 Users Manual", Number = "ANL-95/11 - Revision 2.0.24", Institution = "Argonne National Laboratory", Year = "1999"}
@InProceedings{petsc-efficient, Author = "Satish Balay and William D. Gropp and Lois Curfman McInnes and Barry F. Smith", Title = "Efficienct Management of Parallelism in Object Oriented Numerical Software Libraries", Booktitle = "Modern Software Tools in Scientific Computing", Editor = "E. Arge and A. M. Bruaset and H. P. Langtangen", Pages = "163--202", Publisher = "Birkhauser Press", Year = "1997"}