Latitude is expressed by four figures preceded by the letter L. The first two figures denote the degrees and the last two the minutes. The letter N (north) or S (south) follows if it is needed; however, to keep things simple, the letter may be omitted if there is no risk of confusion.
Example : L3740S—Indicates latitude 37°40’S.
Longitude is expressed by four or, if necessary, five figures preceded by the letter G. The first two (or three) figures denote the degrees and the last two the minutes. When the longitude is more than 99°, no confusion will normally arise if the figure indicating hundreds of degrees is omitted. However, where it is necessary to avoid confusion, the five figures should be used. The letter E (east) or W (west) follows if it is needed; otherwise M it may be omitted, as in the case of latitude.
Example : G13925E—Indicates longitude 139°25’E.