Books can be attributed to "Anonymous" for several reasons:
* They are officially published under that name * They are traditional stories not attributed to a specific author * They are religious texts not generally attributed to a specific author
Books whose authorship is merely uncertain should be attributed to Unknown.
My two favorite verses that have stuck with me: - "In peace I will lie down and sleep, for You alone, God, make me dwell in safety." (Psalm 4:8) - "My flesh and my heart may fail, but God is the strength of my heart and my portion forever." (Psalm 73:26)