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These pages provide you with an example of the layout and style for 100% reproduction which we wish you to adopt during the preparation of your paper. This is the output from the L A T E X document style you requested. Text should be produced within the dimensions shown on these pages: each column 7.5 cm wide with 1 cm middle margin, total width of 16 cm and a maximum length of 20.2 cm on first pages and 21 cm on second and following pages. The L A T E X document style uses the maximal stipulated length apart from the following two exceptions (i) L A T E X does not begin a new section directly at the bottom of a page, but transfers the heading to the top of the next page; (ii) L A T E X never (well, hardly ever) exceeds the length of the text area in order to complete a section of text or a paragraph. 1.1. Spacing We normally recommend the use of 1.0 (single) line spacing. However, when typing complicated mathematical text L A T E X automatically increases the space between text lines in order to prevent sub-and superscript fonts overlapping one another and making your printed matter illegible. 1.2. Fonts These instructions have been produced using a 10 point Computer Modern Roman. Other recommended fonts are 10 point Times Roman, * Footnotes should appear on the first page only to indicate your present address (if different from your normal address), research grant, sponsoring agency, etc. These are obtained with the \thanks command. The most suitable printer is a laser printer. A dot matrix printer should only be used if it possesses an 18 or 24 pin printhead (" letter-quality "). The printout submitted should be an original; a photocopy is not acceptable. Please make use of good quality plain white A4 (or US Letter) paper size. The dimensions shown here should be strictly adhered to: do not make changes to these dimensions, which are determined by the document style. The document style leaves at least 3 cm at the top of the page before the head, which contains the page number. Printers sometimes produce text which contains light and dark streaks, or has considerable lighting variation either between left-hand and right-hand margins or between text heads and bottoms. To achieve optimal reproduction quality , the contrast of text lettering …