Lukewarm or Luke-warm?

In 1991 I published my first book in Norwegian: "Bevare meg vel!" (1). I had preached a sermon in which I focused on the principles I believe Luke built his faith on, and which made him remain faithful, whilst Demas left the ministry. 

The book was meant for new believers, but even mature Christians have found the book helpful. Therefore, I published the book in Russian in 2006 when Magna and I served in Eastern Europe for the first time. The book was published under the name: "Обрести и не утратить" (2)

Since my Russian was and is limited, I translated the Norwegian version into English and had a couple of translators assisting in the translation. In 2008, I made the English version available as a pdf under the title "Lukewarm or Luke-warm?". 
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(1) In Norwegian the title is used as an 'outburst' when people have had a sudden surprise, it litteraly means "Keep me safe!"
(2) The title in Russian translates "Finding and not losing"