# Nested Optional Graph Patterns
@prefix foaf: .
@prefix vcard: .
_:a foaf:name "Alice" .
_:a foaf:mbox .
_:a vcard:N _:x .
_:x vcard:Family "Hacker" .
_:x vcard:Given "Alice" .
_:b foaf:name "Bob" .
_:b foaf:mbox .
_:b foaf:N _:z .
_:z vcard:Family "Hacker" .
_:e foaf:name "Ella" .
_:e vcard:N _:y .
_:y vcard:Given "Eleanor" .