is available only in the sense that the article doesn't accept the number that is available--thus using its own doubts to lend validity to themselves.
The article does not accept the number that is currently available.
It took the sculptors Jean de Marville, Claus Sluter, and Claus de Werve 26 years (from 1385 to 1411) to complete the intricate marble and alabaster sculptures for the extravagant mausoleum of Philippe le Hardi.