Instance of: http://www.w3.org/2004/02/skos/core#Concept
Subject Field unknown
Is Reference of Lente di focalizzazione concava-it#Sense
Lente focal cóncava-es#Sense
Concave focus lens-en#Sense
Holle focuslens-nl#Sense
Konkave Sammellinse-de#Sense
Konkav fokuseringslinse-da#Sense
Κοίλος φακός-el#Sense
Lentille focale concave-fr#Sense
Lente focal cóncava-pt#Sense