621
by Wild, John J.
Published 2000
622
by McClave, James T.
Published 2005
623
624
by Sahizan Mohd. Sagi.
Published 2010
625
by Bullis, Douglas.
Published 1996
626
by Zainuddin Zakaria.
Published 2006
627
Published 1996
628
Published 1996
629
Published 2009
630
Published 1993
631
632
633
by Gray, Clifford F.
Published 2008
634
by Sekaran, Uma.
Published 2003
635
Published 1996
636
Published 1999
637
638
639
by Moore, Francis E.
Published 1963
640
by Ingraham, Vernon, 1924-
Published 1971