query: embed.html#SELECT DISTINCT ?month_int ?monthLabel (?day_int as ?d) ?world_dayLabel (?world_day as ?link) (GROUP_CONCAT(DISTINCT ?countryLabel; separator=", ") as ?countries) WHERE {
  { SELECT ?month_int ?month ?day_int ?world_day ?country WHERE {
  ?month wdt:P31 wd:Q47018901; wdt:P1545 ?month_ordinal.
  ?day p:P361 [ps:P361 ?month; pq:P1545 ?day_ordinal ].
   BIND(xsd:integer(?month_ordinal) AS ?month_int)
   BIND(xsd:integer(?day_ordinal) AS ?day_int)
  VALUES ?type {wd:Q2558684 wd:Q422695} # World ___ day; Awareness day 
  ?world_day wdt:P31 ?type; wdt:P837 ?day
  OPTIONAL {?world_day wdt:P17 ?country} 
  }  }
  SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en".
        ?month rdfs:label ?monthLabel. ?world_day rdfs:label ?world_dayLabel. ?country rdfs:label ?countryLabel }
  } GROUP BY ?month_int ?monthLabel ?day_int ?world_dayLabel ?world_day
  ORDER BY ?month_int ?d