schema.org/Book with multiple authors using JSON-LD [duplicate]

Question

How do I display multiple book authors using JSON-LD?

This question is similar to my original question, but decided to create a different one seeing that 2 different formats are used.

Here is my post using microdata:

schema.org/Book with multiple authors

My question is similar. I have a book with multiple authors. Am I doing it correctly by displaying the author property more than once? Below is the code using JSON-LD:

<script type="application/ld+json">
{
     "@context": "http://schema.org",
     "@type": "WebPage",
     "mainEntity": {
          "@type": "Book",
          "author": {
               "@type": "Person",
               "familyName": "van der Westhuizon",
               "givenName": "Jason",
               "name": "Jason van der Westhuizon"
          },
          "author": {
               "@type": "Person",
               "familyName": "du Toit",
               "givenName": "Jene",
               "name": "Jene du Toit"
          },
          "author": {
               "@type": "Person",
               "familyName": "September",
               "givenName": "Koos",
               "name": "Koos September"
          },
          "bookFormat": "http://schema.org/Paperback",
          "datePublished": "2014-11",
          "inLanguage": "en",
          "isbn": "1234567890123",
          "name": "My Book Name",
          "numberOfPages": "381",
          "publisher": {
               "@type": "Organization",
               "name": "My Publisher"
          },
     }
}
</script>

The reason why I ask is because when I go to Google's structured data tester tool then in the results it only shows one author. Why doesn't it display all 3? Is my code wrong?

Answer 1

your code contains error, thats why two authors aren't recognized. If you have more then one author, you should add them as list without entity duplication. Here the correct code:

<script type="application/ld+json">
{
     "@context": "http://schema.org",
     "@type": "WebPage",
     "mainEntity": {
          "@type": "Book",
          "author": [{
               "@type": "Person",
               "familyName": "van der Westhuizon",
               "givenName": "Jason",
               "name": "Jason van der Westhuizon"
          },
          {
               "@type": "Person",
               "familyName": "du Toit",
               "givenName": "Jene",
               "name": "Jene du Toit"
          },
         {
               "@type": "Person",
               "familyName": "September",
               "givenName": "Koos",
               "name": "Koos September"
          }],
          "bookFormat": "http://schema.org/Paperback",
          "datePublished": "2014-11",
          "inLanguage": "en",
          "isbn": "1234567890123",
          "name": "My Book Name",
          "numberOfPages": "381",
          "publisher": {
               "@type": "Organization",
               "name": "My Publisher"
          }
     }
}
</script>