Help: CS1 errors

==<span id="bad_lccn">Check |lccn= value</span>==
<section begin="bad_lccn_help_text" />{{help desk}}{{#invoke:Cs1 documentation support|help_text_error_messages|err_bad_lccn}}

The {{para|lccn}} parameter is for the [[Library of Congress Control Number]] identifier. It is checked to ensure that the identifier is the proper length and has the correct initial digits.

LCCN is a character string 8–12 characters long. The length of the LCCN dictates the character type of the initial 1–3 characters; the rightmost eight are always digits.<ref>{{cite web |url=https://www.loc.gov/marc/lccn-namespace.html#syntax |title=The LCCN Namespace |website=Network Development and MARC Standards Office |publisher=[[Library of Congress]] |date=November 2003}}</ref>
{|class="wikitable"
|+ LCCN format description
! Length !! Description
|-
| 8 || all characters are digits
|-
| 9 || first character is a lower case letter
|-
| 10|| first two characters are either both lower case letters or both digits
|-
| 11|| first character is a lower case letter, second and third characters are either both lower case letters or both digits
|-
| 12|| first two characters are both lower case letters
|-
|}

Further validation is not performed.

To resolve this error, ensure that the {{para|lccn}} value is correct and that there are no other letters, punctuation, or other characters. 

When receiving this error, be on the lookout for publishers who omitted leading zeros in the LCCN following the two or four digit year. For example, an LCCN that is [https://catalog.loc.gov/vwebv/search?searchCode=LCCN&searchArg=92035247&searchType=1&permalink=y properly 92-035427] could be shortened in the printed work to [https://books.google.com/books?id=3ocPU-S9gloC&q=35247 92-35247]. When experimenting with inserting omitted zeroes, cross-check the finished number against the LCCN permalinks online.

Pages with this error are automatically placed in {{#invoke:cs1 documentation support|help_text_cats|err_bad_lccn|pages=yes}}.<ref group="lower-alpha" name="categories" /><section end="bad_lccn_help_text" />