Q:

Nesting Schema.org 'Person' in 'Article', using Microdata

On a press page I'm using Schema.org’s Article. I tried to add a Person nested within Article, but it did not validate in Google’s Testing Tool.
<ul class="thumbnails" itemscope itemtype="http://schema.org/Article" additionaltype="http://schea.org/Person">
    <li class="row-fluid">
        <a href="#" target="_blank"><div class="sprite"></div></a>
        <div class="span10">
            <h3 itemprop="headline"><span itemprop="name">The Person</span> teams up with <span itemprop="affiliation">THE Company</span> to support <span itemprop="worksFor">The Cause</span></h3>
            <p itemprop="description">Lorem ipsum<span itemprop="jobTitle">floral designer</span> and <span itemprop="jobTitle">model</span> and <span itemprop="jobTitle">mom</span> more text</p>
        </div>
    </li>
</ul>

A:

Well, you are attempting to claim that an Article is also a Person, which doesn't make sense semantically. If you are trying to claim that Person is an author of Article, there is an 'author' property of Article to do this. The additonaltype property is only useful when you are dealing with 'nested' types -- in other words, the properties you specify are common to both items. Obviously, an article and a person don't have many properties in common.
Secondly, additionaltype is a property, so you should specify it as follows:
<ul class="thumbnails" itemscope itemtype="http://schema.org/Article">
<meta itemprop="additionaltype" content="http://schema.org/Person">

That said, I'm not sure whether any search engines support this property, so I wouldn't necessarily recommend its use. If there are properties you don't want explicitly printed, you can still repeat them in meta tags for each item you are using.

