The User's View Level of the GOQL Graphical Query Language. - Euclid Keramopoulos; Philippos Pouyioutas; Tasos Ptohos (IV, 1999)

A Formal Definition of the Users View (UV) of the Graphical Object Query Language (GOQL). - Euclid Keramopoulos; Philippos Pouyioutas; Tasos Ptohos (IV, 2002)

The System Architecture of the GOQL Language. - Euclid Keramopoulos; Tasos Ptohos; Philippos Pouyioutas (Databases and Applications, 2004)

Implementation of the GOQL Language. - Euclid Keramopoulos; Philippos Pouyioutas; Tasos Ptohos (IV, 2004)

The GOQL Language and its Formal Specifications. - Euclid Keramopoulos; Philippos Pouyioutas; Tasos Ptohos (Int. J. Comput. Sci. Appl., 2008)