  A strengthened and generalized version of the standard Virtual Work Principle
is shown to imply, in addition to bulk and boundary balances, a one-to-one
correspondence between surface and edge hypertractions and hyperstrestress
fields in second-grade continua. When edge hypertractions are constitutively
taken null, the hyperstress is shown to take the form it has for a
Navier-Stokes$-\alpha$ fluid, a relevant example of second-grade fluid-like
material.
