https://vocabularyserver.com/dtic/https://vocabularyserver.com/dtic/xml.php?skosTema=1220ATOMIC ENERGY LEVELS https://vocabularyserver.com/dtic/xml.php?skosTema=1220 GROUND STATE NT https://vocabularyserver.com/dtic/xml.php?skosTema=1220 ATOMIC STRUCTURE BT https://vocabularyserver.com/dtic/xml.php?skosTema=1220 ENERGY LEVELS BT