Muroboku-cho period?

[Mikaveli]

In Clive Sinclair's book, "Samurai Swords: A collectors guide" there's a reference to the Muroboku-cho period, where I'd expect the Muromachi period.

 

Now, at first I assumed it was a typo, but then wondered if it could be an alternative way of referring to it?

 

From what I know of the Kanji, 

 

室町時代 (read Muromachi Jidai - period)

 

南北朝 (read Nanbokuchou)

 

So plausibly:

 

室北朝 (Muro Northern court?)

 

But I can't find any references to it that way, assuming I've selected the right Kanji?

[ckaiserca]

The only return on "Muroboku-Cho" on a Google search is a reference to the book by Clive Sinclair you mentioned in your post. That is fairly telling.