[2] Darbo G.: 
Teoria dell’ omologia in una categoria di mappe plurivalenti ponderate. Rend. Sem. Mat. Univ. Padova 28 (1958), 188-224. 
MR 0105093 | 
Zbl 0097.38704[3] Darbo G.: 
Sulle coincidenze di mappe ponderate. Rend. Sem. Mat. Univ. Padova 29 (1959), 256-270. 
MR 0126284 | 
Zbl 0089.39001[4] Darbo G.: 
Estensione alle mappe ponderate del teorema Lefshetz sui punti fissi. Rend. Sem. Mat. Univ. Padova 31 (1961), 46-57. 
MR 0137119[5] Fournier G., Górniewicz L.: 
The Lefschetz fixed point theorem for some non-compact multivalued maps. Fundamenta Mathematicae 94 (1977). 
MR 0436123[6] Górniewicz L.: 
Topological fixed point theory of multivaled mappings. Kluwer, 1999. 
MR 1748378[7] Górniewicz L.: 
Homological methods in the fixed point theory of multivalued maps. Dissertationes Math., Warszawa 129 (1976). 
MR 0394637[8] Granas A.: Generalizing the Hopf-Lefschetz fixed point theorem for non-compact ANR-s. Symposium on Infinite Dimensional Topology, Bâton-Rouge, 1967.
[9] von Haeseler F., Skordev G.: 
Borsuk-Ulam theorem, fixed point index and chain approximation for maps with multiplicity. Pacific J. of Math. 153, 2 (1992), 369-396. 
MR 1151567[10] Jerrard R.: 
Homology with multivalued functions applied to fixed points. Trans. AMS 213 (1975), 407-428. 
MR 0380778[11] Jodko-Narkiewicz S.: Topological degree of weighted mappings. UMK Toruń, 1989, (in Polish).
[12] Pejsachowicz J.: 
Relation between the homotopy and the homology theory of weighted mappings. Bollettino U. M. I. 15-B (1978), 285-302. 
MR 0515493 | 
Zbl 0391.55009[13] Pejsachowicz J.: 
The homotopy theory of weighted mappings. Bollettino U. M. I. 14-B (1977), 702-720. 
MR 0500939 | 
Zbl 0452.55006