A review of the path integral approach to quantum cosmology and its relation
to canonical quantisation. The initial derivation of the Hartle-Hawking and
Vilenkin wavefunctions from the Euclidean Einstein-Hilbert action, and later,
from the Lorentzian path integral using Picard-Lefshets Theory is discussed.
Path integral quantisation of the Einstein-Cartan action is then employed to
obtain the wavefunctions for minisuperspace closed FRW universes dominated by
matter and radiation. These calculations are complimentary to those recently
carried out by Magueijo using canonical quantisation of the same action.