White papers, green papers, treaties, government responses, draft bills, reports from royal commissions, reports from independent inquiries and various government organisations can be released as command papers, so called because they are presented to Parliament formally "By His Majesty's Command".
Command papers are numbered. Since 1870 they have been prefixed with an abbreviation of "command" which has changed over time to allow for new sequences.
^The Australian Guide to Legal Citation. Third Edition. Melbourne University Law Review Association Inc. Melbourne Journal of Law International Inc. Melbourne. 2010. Page 248.