Complex sentence: A six-issue fan magazine, "Marvelmania Magazine", followed the test issue issue and newsletter, the first (titled "Marvelmania Monthly Magazine") dated April 1970 and the last, undated, released in early 1971 and carrying a 1970 copyright.
Split into simpler sentences: A six-issue fan magazine, "Marvelmania Magazine", followed the test issue issue and newsletter. The first issue, titled "Marvelmania Monthly Magazine", was dated April 1970 in its indicia; the last issue, undated, was released in early 1971 and carried a 1970 copyright.