and its potential in theoretical analysis and practical
application has been widely underestimated (see, for example, Nambiar 1997;
Nambiar & Keating 1970; Malik 1970; Linsay & Rooney 1992; Fuchs 1992; Mitrouli
& Koukouvinos 1997). For example, Nambiar & Keating (1970) conclude their paper
by saying