Category:CS1 errors: ISBN date

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This is a tracking category for book and encyclopedia citations implemented with {{citation}} templates and for book and encyclopedia citations implemented with {{cite book}} and {{cite encyclopedia}} that have |isbn= and when the publication date is before 1965.

Help desk

ISBNs were created c. 1965. Books published before that date will not have been issued an ISBN.

To resolve this error:

remove the ISBN when citing a source published before 1965

if the edition of the cited book was published after 1965, ensure that |date= or |year= has the correct publication year

Pages with this error are automatically placed in Category:CS1 errors: ISBN date.