Malta & Gozo islands : Mediterranean Sea / surveyed by Lieut.s Mansell, Wilkinson, & Drew; J. Stokes, master, & J. Millard, second master; H.M.S.s Volage & Medina under the direction of captains T. Graves, R.N. & T. A. B. Spratt, R.N. C.B. F.R.S. 1863