PHPCR references vs. children

I want to migrate my legacy shop system from a relational system to a document based. The reason is obivious: I want to reduce the complexity of relations which describes a shop article, that can have multiple different properties.

So I read the documentation of Doctrine PHPCR and found out, that there are several examples of how to build a model with references, because the main concepts of PHPCR are

• Hierarchy mapping
• References

as described here: Assocation Mapping

But the documentation uses both concepts for the same goal:

References: Article with author and comments as references

Example: Working with Objects

The article is queried by its ID/path: /article/hello-world, the comments and the author are references.

/**
 * @ReferenceOne
 */
private $author;

/**
 * @Referrers(referrerDocument="Comment", referencedBy="article")
 */
private $comments;

Hiearchical: Blog user as child document

Example: The QueryBuilder

It queries the blog user (propably author) by path

$qb->from('Blog\User', 'u');

// where name is "daniel"
$qb->where()
  ->eq()->field('u.name')->literal('daniel');

Therefore, my main question is, what could be the reason for that, or to be more specific, what are the best practices to build up a model with dynamic properties like a shop article?

/article/id:properties[A|B|C]

or

/article/id/propertyA
/article/id/propertyB
/article/id/propertyC

It would be really helpful If someone shares its experience.

I found an answer by myself:

• Use hierarchical references when you want to move documents and rearrange the structure
• Use references to describe/extend the document

For shop articles, its better to use references for properties like name, price, tax ea. and children if you want to have sub articles like bundles.