selected Guy Davis bibliography: 

B.P.R.D., The Marquis, The Nevermen
  Sandman Mystery Theater, Baker Street

further information on Guy Davis: 

guydavisartworks.com

character: 

Horace Rumpole appears in a series of books
  twritten by John Mortimer

further information on the Rumpole and Mortimer: 

en.wikipedia.org/wiki/John_Mortimer