Syed Adnan Haider Ali Shah Bukhari  , 
    On Word Equation of the Form <IMG SRC=http://medwelljournals.com/fulltext/jeas/Image12.gif>
In a Free Semigroup: A Further Extension,
    Journal of Engineering and Applied Sciences,
    Volume 2,Issue 5,
    2007,
    Pages 874-876,
    ISSN 1816-949x,
    jeasci.2007.874.876,
    (https://makhillpublications.co/view-article.php?doi=jeasci.2007.874.876)
    Abstract: Word equations of the form <IMG SRC=http://medwelljournals.com/fulltext/jeas/Image13.gif> are concerned in this study. In particular, I investigate the case where x is of different length than Z<SUB>i</SUB>, for any i and k and k<SUB>i</SUB> are at least 3, for all powers of the same word for all 1 i n. It is also shown that this result implies a well-known result by Appel and Djorup about the more special case where k<SUB>i </SUB>= k<SUB>j</SUB> for all 1 i< j n.
    Keywords: Word equations; Appel and Djorup’s result