January 1961 - missing cover

August 1962 - missing cover 

November 1964 - Cover has some tearing/creasing

August 1978 - Cover intact, good condition

July 1979 - Cover torn half way down to bottom but still present

October 1979 - Cover torn/separated from spine top 1/3 

November 1979 - Cover missing

February 1983 - Cover has wear along spine but still intact

September 1985 - Cover intact, good condition

November 1988 - Cover intact, good condition

September 1991 - Cover intact, good condition 

Please ask questions prior to purchasing.