Note: The suffix Z (Zulu) appearing in some of the documents indicates Greenwich Mean Time (GMT). Messages with time indicated as a.m. or p.m. refer to Washington time (five hours earlier than Greenwich). The date/time group used in messages employs the 24 hour clock and can be understood by the following example. In the date/time group 021305Z AUG 64; 02 refers to the day of the month; 1305 means the time, in this case 1:05 p.m; Z refers to the time zone; and AUG 64 means August 1964. Variants of date/time groups are common. For example, some may also be preceded by a Z and not include the month and year as in the case of Z021305Z.