#### Volume 11, issue 1 (2011)

 1 A Adem, J Leida, Y Ruan, Orbifolds and stringy topology, Cambridge Tracts in Math. 171, Cambridge Univ. Press (2007) MR2359514 2 A Adem, Y Ruan, Twisted orbifold $K$–theory, Comm. Math. Phys. 237 (2003) 533 MR1993337 3 M Atiyah, G Segal, On equivariant Euler characteristics, J. Geom. Phys. 6 (1989) 671 MR1076708 4 B Blackadar, $K$–theory for operator algebras, MSRI Publ. 5, Cambridge Univ. Press (1998) MR1656031 5 J Bryan, J Fulman, Orbifold Euler characteristics and the number of commuting $m$–tuples in the symmetric groups, Ann. Comb. 2 (1998) 1 MR1682916 6 W Chen, Y Ruan, Orbifold Gromov–Witten theory, from: "Orbifolds in mathematics and physics (Madison, WI, 2001)" (editors A Adem, J Morava, Y Ruan), Contemp. Math. 310, Amer. Math. Soc. (2002) 25 MR1950941 7 L Dixon, J A Harvey, C Vafa, E Witten, Strings on orbifolds, Nuclear Phys. B 261 (1985) 678 MR818423 8 C Farsi, C Seaton, Generalized twisted sectors of orbifolds, Pacific J. Math. 246 (2010) 49 MR2645879 9 C Farsi, C Seaton, Nonvanishing vector fields on orbifolds, Trans. Amer. Math. Soc. 362 (2010) 509 MR2550162 10 F Hirzebruch, T Höfer, On the Euler number of an orbifold, Math. Ann. 286 (1990) 255 MR1032933 11 S Illman, The equivariant triangulation theorem for actions of compact Lie groups, Math. Ann. 262 (1983) 487 MR696520 12 K Kawakubo, The theory of transformation groups, The Clarendon Press, Oxford Univ. Press (1991) MR1150492 13 I G Macdonald, The Poincaré polynomial of a symmetric product, Proc. Cambridge Philos. Soc. 58 (1962) 563 MR0143204 14 I Moerdijk, Orbifolds as groupoids: an introduction, from: "Orbifolds in mathematics and physics (Madison, WI, 2001)" (editors A Adem, J Morava, Y Ruan), Contemp. Math. 310, Amer. Math. Soc. (2002) 205 MR1950948 15 I Moerdijk, J Mrčun, Introduction to foliations and Lie groupoids, Cambridge Studies in Advanced Math. 91, Cambridge Univ. Press (2003) MR2012261 16 I Moerdijk, D A Pronk, Simplicial cohomology of orbifolds, Indag. Math. $($N.S.$)$ 10 (1999) 269 MR1816220 17 S S Roan, Minimal resolutions of Gorenstein orbifolds in dimension three, Topology 35 (1996) 489 MR1380512 18 Y Ruan, Stringy geometry and topology of orbifolds, from: "Symposium in Honor of C H Clemens (Salt Lake City, UT, 2000)" (editors A Bertram, J A Carlson, H Kley), Contemp. Math. 312, Amer. Math. Soc. (2002) 187 MR1941583 19 I Satake, The Gauss–Bonnet theorem for $V$–manifolds, J. Math. Soc. Japan 9 (1957) 464 MR0095520 20 C Seaton, Two Gauss–Bonnet and Poincaré–Hopf theorems for orbifolds with boundary, Differential Geom. Appl. 26 (2008) 42 MR2393971 21 H Tamanoi, Generalized orbifold Euler characteristic of symmetric products and equivariant Morava $K$–theory, Algebr. Geom. Topol. 1 (2001) 115 MR1805937 22 H Tamanoi, Generalized orbifold Euler characteristics of symmetric orbifolds and covering spaces, Algebr. Geom. Topol. 3 (2003) 791 MR1997338 23 W P Thurston, The geometry and topology of three-manifolds, Princeton Univ. Math. Dept. Lecture Notes (1979) 24 A Verona, Triangulation of stratified fibre bundles, Manuscripta Math. 30 (80) 425 MR567218 25 W Wang, Equivariant $K$–theory, wreath products, and Heisenberg algebra, Duke Math. J. 103 (2000) 1 MR1758236 26 W Wang, J Zhou, Orbifold Hodge numbers of the wreath product orbifolds, J. Geom. Phys. 38 (2001) 152 MR1823666 27 C T Yang, The triangulability of the orbit space of a differentiable transformation group, Bull. Amer. Math. Soc. 69 (1963) 405 MR0146291 28 E Zaslow, Topological orbifold models and quantum cohomology rings, Comm. Math. Phys. 156 (1993) 301 MR1233848 29 J Zhou, Delocalized equivariant coholomogy of symmetric products arXiv:math/9910028