Error "The publication '[Name]' does not exist." running sp_article_validation

DECLARE @p SYSNAME, @a SYSNAME
SET @p = N'[NAME]'
SET @a = N'[ARTICLE]'

EXEC sp_article_validation @p,@a

I'm using the exact name of the publication provided by the table MSpublications (even using NAME or QUOTENAME(N'Name') generates the same error), yet it's saying it doesn't exist. Note that it doesn't work with any other publications either. Yet this is what sp_article_validation (Transact-SQL) says.

SELECT publication
FROM MSpublications
ORDER BY publication