; &gt;
&gt; &gt; | Denning, P.J., Dennis, J.B., Qualitz, J.E.,
&gt; &gt; |'Machines, Languages, and Computation',
&gt; &gt; | Prentice-Hall, Englewood Cliffs, NJ, 1978.
&gt; 
&gt; This reference is not available to me.
&gt; Would you state the definition of language
&gt; that the text presents?

As far as online stuff, MathWorld is gone.
Google gave 4000 hits, mostly course syllabi.

Try:

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