How to design constructor with variable parameters?

Question

I'm working on a "project" where I need to make a class "book" that can store information about a book. It's name, isbn, stock, etc... What is throwing me off a little bit is the author. I'm allowed to enter up to 4 authors per book object. I'm coming at the problem with the assumption, that I should be able to load this author data within the constructor. Questions is how. At first I thought I'd make 4 different constructors, each with a different number of author parameters. Simple enough but it seems unnecessarily messy. Then I thought I'd make a variable length parameter array. e.g book( String ... author ). But what if someone wants to enter more than 4 authors or none at all?
QUESTION:
Is there a way I can set a minimum and maximum of inputs for variable length paramters?
Vectors seem like they could be useful here instead of arrays. But again there is that problem of controlling constructor parameters.

Answer 1

Then I thought I'd make a variable length parameter array. e.g book( String ... author ). (Otherstuff, String author, String ... otherAuthors)
Is there a way I can set a minimum and maximum of inputs for variable length paramters?Validate it in the code itself
Or create another class specifically for Authors
No matter what you do you will still need validation code, for example what if the author is null? Or empty?
     class Authors
            public String Author1;
            public String Author2;
            public String Author3;
            public String Author4;
            public Authors(String auth)
            public Authors(String auth1, String auth2)
       }