Dear Friends,

I need help with a result due to Levitan.

Please see the last paragraph of page 4 of the following paper: http://www.emis.de/journals/EJDE/2007/163/rath.pdf

Above, is the set of continuous functions bounded below and above by (here is a positive constant less than ) and , respectively, and that .Originally Posted byAuthor

I really need help about finding abookreference forLevitan's result.

Many thanks!

bkarpuz