Jürgen Albert Hermann A. Maurer Grzegorz Rozenberg Simple EOL Forms under Uniform Interpretation Generating CF Languages. 1-14 1978 conf/icalp/1978 ICALP db/conf/icalp/icalp78.html#AlbertMR78 http://dx.doi.org/10.1007/3-540-08860-1_1