@ARTICLE {SVF94,
   ANNOTE = {MR95d:65030},
   AUTHOR = {Sleijpen, G. L. G. and van der Vorst, H. A. and Fokkema, D. R.},
    TITLE = {$\mbox{\rm {B}i{C}{G}stab}(\ell)$ and 
            other hybrid {B}i-{C}{G} methods},
  JOURNAL = {Numer. Algorithms},
 FJOURNAL = {Numerical Algorithms},
   VOLUME = {7},
     YEAR = {1994},
   NUMBER = {1},
    PAGES = {75--109},
     ISSN = {1017-1398},}