. . . . . . . . . . "Martin Erler"@en . . . . . . . . . . . . . . . "30736497"^^ . . . . . . . . . "7286"^^ . . "Martin Erler (c. 1920 - 11 August 2014) was a German philatelist who was an expert on the revenue stamps of Germany who with John A. Norton (died June 1980) wrote the only comprehensive catalogue of German revenue stamps."@en . . . . . . . . . . . . . . . . . . "Martin Erler (c. 1920 - 11 August 2014) was a German philatelist who was an expert on the revenue stamps of Germany who with John A. Norton (died June 1980) wrote the only comprehensive catalogue of German revenue stamps."@en . . . . . "1093260223"^^ . . . . .