PUBLISHERS were warned yesterday not to reproduce government maps without permission. Protection of copyright is being stepped up by the Government in an attempt to curb unauthorised reproduction of official mapping materials in books, magazines and newspapers, said Mr Gordon Andreassend, principal land surveyor and head of the Survey andMapping Office. The Government collected three times more cash from map royalty fees in the last financial year than in the one before, it was also announced yesterday. Ignorance of copyright laws would not be accepted as an excuse for unlawful publishing and permission had to be sought before publication, Mr Andreassend said. But he stressed that permission was usually granted after payment of royalty fees with the requirement that an acknowledgment be included specifying the source of the map. Occasionally royalties would be discounted or waived, he said. The Survey and Mapping Office produces a series of maps, aerial photographs, tourist directories and leisure guides covering Hongkong, which are sold throughout the territory.