Guide: Page Numbers
Only items that are published with printed paper have pages. All of these items are printed in the book form such as commercial comics (whole and excerpt) and doujinshi have pages and therefore have a page number. Single paged items, while not always appropriate to consider as doujinshi, such as hand-drawn sketches, are still published on paper and therefore have a page number (most likely of 1 for front only paper and 2 if front and back contain writing).
CG collections of any type, shitajiki, clear files, posters, telephone cards (tereka) do not have pages. Therefore, no number should be entered for page number.
There are various ways to number the pages of a book and, while most methods arrive should arrive at a similar number, there are some methods to completely avoid.
METHOD TO NUMBER THE PAGES OF DOUJINSHI
First, distinguish offset doujinshi from copy book doujinshi (cf. TYPE explaination article for details). Offset books usually have no printing on the inside and outside covers. They also may have some decorative filler pages between either covers, sometimes both, and are those pages which contain no drawings or writings. Some offset books do have content on the inside front of back covers, so it is always best to check against an original copy of the book or to pay especial attention to the enumeration within the book. Some doujinshi have color pages, especially near the front, that are blank on their backs. Such blank pages behind a full color page should be considered when numbering a doujinshi's pages.
Doujinshi often have a numbering system within the book whereby the page number is printed every page or some of the pages. The front cover is often considered as the first page and the inside front cover, although often blank, is considered the second page. The aformentiond 'decorative filler page', if it exists, is almost never enumerated. Often, the first interior page of the book is considered as page 3. From there on, the enumeration proceeds in the usual order of the natural numbers until reaching the end of the interior pages, an even number. Then, the inside back cover, usually blank, and the back cover are considered the final two pages.
Some books express their own internal numbering system differently. The usually encountered alternative is when the first interior page, viz. the first page subsequent to the inside front cover that contains drawing or writing, is considered as page 1. By the time the reader reaches the final interior page, the page immediatly preeceding the inside back cover, the question arises, 'should I consider the inside back cover and back cover as two extra pages?'. To avoid this question althougher, I dispense with the interal page enumeration and consider the front cover, inside front cover, inside back cover and back cover as consitituting four pages, similar to the method listed above.
Regarless of what system a data submitter wishes to use an offset doujinshi should almost always have an even number of pages.
Copy books can be a different matter altogether. Since they are printed cheaply on paper from a copy machine and held together with staples, it is possible for a copy book to have an odd number of pages. I've come across at least three different types of copy books. (1) pages are printed one one side of the page leaving a blank back side. Such books are easy to count. Simply count the front sides which contain the content and ignore the back sides. (2) two seperate pages of a book are printed on one side of a large piece of paper and then the paper is folded in half and the various papers are bound together. Such a book is similar to the offset publication however the inside back and inside front covers often have writings and therefore should be numbered. (3) pages are nicely printed and front cover and back covers exist with blank inside frond and inside back covers, however the book is bound cheaply with staples. I've only come across one such book, a resident evil parody, which happened to also have a color drawing cut out by hand and glued to the front cover, which consisted of rather thick black paper. I would recommend using the method for counting pages appropriate for the offset publication.
METHOD TO COUNT PAGES IN A COMMERCIAL BOOK
Commercial works often differ from doujinshi in that they have a book-cover that is not glued or attached in any secure way to the binding of the book. This book-cover has five main parts (1) front cover (2) back cover (3) spine between front and back covers (4) flap that attches to front cover and folds between inside front cover and first interior page and (5) flap that attches to back cover and foldes between inside back cover and last interior page. This book-cover may be flattened out into one single sheet of paper and, if done as such, has printing on only one side and is blank on the other. This complex book-cover makes counting troublesome in the usual way listed for doujinshi. (Note, due to the irregular nature of doujinshi, there are doujinshi, such as Galaxist's Cham Is Oreno (ãƒãƒ£ãƒ isä¿ºã®) that has a similar book cover although the back of that cover is also illustrated with artwork.)
The book-cover itself wraps around another front cover, back cover, spine complex that binds the intrior pages usually with glue together. This secondary cover is similar to the only cover usually found on offset doujinshi. Once again, the question of how to number such a cover arises.
Commercial books also have an official page count that is listed on book selling websites such as amazon.co.jp. (Toranoana lists pages numbers as well for the comparitively few doujinshi that it does sell and may be used similarly. ) Rather than try to conflict with the official count, which is easy to find and corresponds to the internal numbering in the book, I use the numbering convention within the book as the guide to determine the total page count to enter into the database.
WHAT TO AVOID
If you must reference a scan, rather than the original publication, check for missing pages. This can most easily be done by looking for the numbering convention used within a book and then, using that convention, counting foward or backward through the pages one-by-one. If you start on page 1 and then count four pages ahead, you should be on page 5. If the page says 6, then, most likely, you have an incomplete scan. Therefore, your data will be incomplete. Check your original book to see if you missed scanning a page (for your personal records), check online for data about the book (use google.co.jp and search the title, circle, author, etc.), or, even better, buy a copy of the actual book and check against that.