APA

HELDMAN R. K., . (1994). INFORMATION TELECOMMUNICATION: NETWORKS, PRODUCTS AND SERVICES. NEW YORK: MCGRAW-HILL.

Chicago

HELDMAN ROBERT K, . 1994. INFORMATION TELECOMMUNICATION: NETWORKS, PRODUCTS AND SERVICES. NEW YORK: MCGRAW-HILL.

Harvard

HELDMAN R. K., . (1994). INFORMATION TELECOMMUNICATION: NETWORKS, PRODUCTS AND SERVICES. NEW YORK: MCGRAW-HILL.

MLA

HELDMAN ROBERT K, . INFORMATION TELECOMMUNICATION: NETWORKS, PRODUCTS AND SERVICES. NEW YORK: MCGRAW-HILL. 1994.