Retrieve all individuals based on Data Property Assertions

Question

I am trying to retrieve information based on Data Property Assertions in Protege (SPARQL Query), however, my code is not working. I am trying to get all individuals that were born after 1960.

PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX owl: <http://www.w3.org/2002/07/owl#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>

SELECT ?person ?birthYear
WHERE {
  ?a rdfs:label ?person .
  ?person xsd:hasBirthYear ?birthYear .
  FILTER(?birthYear>=1960)
}