Help:ISBN links
For a book with ISBN e.g. 0131103628, the simple wikitext "ISBN 0131103628" gives ISBN 0131103628, with the same target as Special:Booksources/0131103628: the text of MediaWiki:Booksourcetext and links regarding the book according to the contents of the page "Book sources" in the project namespace (ns4, here: Meta), where each occurrence of MAGICNUMBER is replaced with the ISBN.
If there is no such "Book sources" page, a default page is displayed. It uses the settings $wgBookstoreListEn in Language.php, currently:
/* private */ $wgBookstoreListEn = array( "Amazon.com" => "http://astore.amazon.com/amazon-books-20/detail/$1" "Amazon.de" => "http://astore.amazon.de/www.amazon.de-21/detail/$1" "Amazon.fr" => "http://astore.amazon.fr/www.amazon.fr-21/detail/$1" "Amazon.co.uk" => "http://astore.amazon.co.uk/www-amazon-co-uk-21/detail/$1" "AddALL" => "http://www.addall.com/New/Partner.cgi?query=$1&type=ISBN", "PriceSCAN" => "http://www.pricescan.com/books/bookDetail.asp?isbn=$1", "Barnes & Noble" => "http://shop.barnesandnoble.com/bookSearch/isbnInquiry.asp?isbn=$1", );
The name of the book sources page can be changed by editing MediaWiki:Booksources, but the name space cannot.
Alternative
Use a template like Template:ISBN allowing {{ISBN|193151447X}} to produce something like:
However, often a separate page would be desirable. This can be done, but requires a page like 193151447X for every book. Those pages can call Template:Bk, so that they only have to contain {{bk}}.