  The well-known problem of unidirectional plane flow of a fluid in a
half-space due to the impulsive motion of the plate it rests upon is discussed
in the context of the second-grade and the Oldroyd-B non-Newtonian fluids. The
governing equations are derived from the conservation laws of mass and momentum
and three correct known representations of their exact solutions given. Common
mistakes made in the literature are identified. Simple numerical schemes that
corroborate the analytical solutions are constructed.
