No other book...

[Itasan]

Which is (are) correct?
1. No book in Japan is as popular as comics.
2. No books in Japan are as popular as comics.
3. No other book in Japan is as popular as comics.
4. No other books in Japan are as popular as comics.
Thank you.

[Casiopea]

1. No book in Japan is as popular as comics.
=> If 'No' is synonymous with not one, OK.

2. No books in Japan are as popular as comics.
=> If 'No' is synonymous with not any, OK.

3. No other book in Japan is as popular as comics.
=> Here we have the opposite meaning: "No other book" refers to a specific book that is more popular than comics.

4. No other books in Japan are as popular as comics.
=> Same as 3. but plural: specific books that are more popular than comics.

What about?

There isn't one book in Japan that is as popular as comics.
No one book in Japan is as popular as comics.

Mind you, Harry Potter is an exception, right?