query: #Map of places of birth of dead sociologists, colour-coded by era
  #defaultView:Map
  SELECT DISTINCT ?person ?name ?birthplace ?birthyear ?coord ?layer WHERE {
    { ?person wdt:P106 wd:Q2306091. }
    UNION
    { ?person wdt:P101 wd:Q21201. }
    ?person wdt:P570 ?dod.
    ?person wdt:P19 ?place.
    ?place wdt:P625 ?coord.
    OPTIONAL { ?person wdt:P569 ?dob. }
    BIND(YEAR(?dob) AS ?birthyear)
    BIND(IF(?birthyear < 1700, "Pre-1700", IF(?birthyear < 1751, "1700-1750", IF(?birthyear < 1801, "1751-1800", IF(?birthyear < 1851, "1801-1850", IF(?birthyear < 1901, "1851-1900", IF(?birthyear < 1951, "1901-1950", "Post-1950")))))) AS ?layer)
    ?person rdfs:label ?name.
    ?place rdfs:label ?birthplace.
    FILTER((LANG(?name)) = "en")
    FILTER((LANG(?birthplace)) = "en")
  }
  ORDER BY ?birthyear