Lindelöf covering theorem

== English == === Etymology === Named after Ernst Leonard Lindelöf (1870–1946), a Finnish mathematician. === Proper noun === Lindelöf covering theorem (topology) A theorem which states that for any open covering of some given set in Euclidean n-space there is an open subcovering (of that same set) which is countable. === References === Tom M. Apostol (1957), Mathematical Analysis : A Modern Approach to Advanced Calculus, Reading, Massachusetts, U.S.A.: Addison-Wesley Publishing Company, Inc., published 1960, LCCN 57008707, §3-7, page 54