Malmesbury's Chronicle dates from ca. 1125. There are at least six major distinctive revisions and rewrites of the Malmesbury manuscripts. In addition to a revision around the year 1230, other variants bear the letters B, C, L, M, and T which are simply letters to indicate where the manuscripts are housed. There are other hybrids described as things like CL which indicates that C was written using L as its base. 

Excerpts from translation by Rev. John Sharpe (1815), edit by J.A. Giles (1904)