zed balanced stochastic truncation.
      Proc. 29-th CDC, Honolulu, Hawaii, pp. 476-481, 1990.

  [4] Varga A.
      Balancing-free square-root algorithm for computing
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      Proc. 30-th IEEE CDC,  Brighton, Dec. 11-13, 1991,
      Vol. 2, pp. 1062-1065.

</PRE>
<A name="Numerical Aspects"><B><FONT SIZE="+1">Numerical Aspects</FONT></B></A>
<PRE>
  The implemented methods rely on accuracy enhancing square-root or
  balancing-free square-root techniques. The effect