Usually consulting whatthefont and identifont to come to results, time and time again a little help from typophile also comes handy and highly appreciated.
unfortunately i have not come across any copy of the cover which is neither low res, blurred or distorted. Thus, automated research is not effective.
original cover was first produced in 1967 (so as to give YOU an idea when the font in question was created)
letters that do stand out are K, Y and up to a point S.
thanks for the help provided!