sentences: "The Handbook", as it was often cited, was itself a much enlarged and revised version of H.F. Witherby's "Practical Handbook of British Birds" (published between 1919 and 1924 as two volumes in three parts).Some of the plates were by Marinus Adrianus Koekkoek the Younger and were licensed after they were painted for "Ornithologia Neerlandica, de vogels van Nederland" by Eduard Daniel van Oort (published 1922-1935).