D H Gottlieb,
Covering transformations and universal fibrations,
Illinois J. Math. 13 (1969) 432 MR0239595
3
D H Gottlieb,
The trace of an action and the degree of a map, Trans.
Amer. Math. Soc. 293 (1986) 381 MR814928
4
D H Gottlieb,
Self coincidence numbers and the fundamental grouparXiv:math.AT/0702236
5
W Lück, Dimension
theory of arbitrary modules over finite von Neumann algebras
and $L^2$–Betti numbers. I. Foundations, J. Reine Angew.
Math. 495 (1998) 135 MR1603853
6
W Lück, Dimension
theory of arbitrary modules over finite von Neumann algebras
and $L^2$–Betti numbers. II. Applications to Grothendieck
groups, $L^2$–Euler characteristics and Burnside groups, J.
Reine Angew. Math. 496 (1998) 213 MR1605818
7
W Lück,
$L^2$–invariants: theory and applications to geometry and
$K$–theory, Ergebnisse der Mathematik und ihrer
Grenzgebiete 44, Springer (2002) MR1926649
8
T Schick,
$L^2$–determinant class and approximation of $L^2$–Betti
numbers, Trans. Amer. Math. Soc. 353 (2001) MR1828605