APA

Held (Gilbert), . (1996). Understanding Data Commuinications. Ed 4. : .

Chicago

Held (Gilbert), . 1996. Understanding Data Commuinications. Ed 4. : .

Harvard

Held (Gilbert), . (1996). Understanding Data Commuinications. Ed 4. : .

MLA

Held (Gilbert), . Understanding Data Commuinications. Ed 4. : . 1996.