Bibliography abbreviations are commonly used in academic writing to save space and time. IBID is an abbreviation for the Latin term 'ibidem, ' which means 'in the same place.' AUTH is an abbreviation for 'AUTHOR, ' ETAL is an abbreviation for 'et alii, ' which means 'and others, ' ETSEQ is an abbreviation for 'et sequentes, ' which means 'and the following, ' and OPCIT is an abbreviation for 'opere citato, ' which means 'in the work cited.'