Postal stationery can be overprinted by the government or, occasionally, by a private overprint. The first stamps were overprinted German and Bavarian stamps. In 1947, stamps of Sarawak were overprinted with the British royal monogram. In 1922, stamps were overprinted to commemorate the Malaya-Borneo Exhibition. In 1898, stamps of Perak were overprinted "Pahang". In addition to stamps, postal stationery items were also overprinted and made available. Three additional stamps overprinted in Greek currency arrived on 24th. Stamps have occasionally been overprinted multiple times. Some British revenue stamps were also overprinted for use in the colonies. In each case five panes of 50 stamps were overprinted with the initials "I.R.". After the Japanese occupation in 1941, stamps were overprinted by the Japanese forces. In that year, stamps of Gabon and Middle Congo were overprinted . In 1881, stamps of the Strait Settlements were overprinted "Sungei Ujong". Beginning in May 1894, the stamps of North Borneo were overprinted "LABUAN". They were also overprinted for use as revenue stamps.