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

ISBN / Date incompatibility

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.^[a]