The Gold Label LIbrary

I saw these at AFKN, did not see the series at SCN. In 1956 a series of 152 of these were issued.   I can only speculate that the new stations that did not have the early P- popular series were sent greatest hits versions of the early library material.  There were many non documented series other than P, W, SP, R, L and misc. 

There was a Standard library series that I never saw in the field, these are the ones with a powder blue label.  100 sides wiith 600 tracks. these were series P-S (Pop) W-S (Western)