Question: Name a relativistic wave equation that contains the word " equation" in its name
SPARQL (Wikidata): SELECT DISTINCT ?sbj ?sbj_label WHERE { ?sbj wdt:P31 wd:Q7310838 . ?sbj rdfs:label ?sbj_label . FILTER(CONTAINS(lcase(?sbj_label), 'equation')) . FILTER (lang(?sbj_label) = 'en') } LIMIT 25