Obstruction classes of crossed modules of Lie algebroids and Lie groupoids linked to existence of principal bundles
Obstruction Theory in Model Categories
Obstruction theory on 8-manifolds
Obstructions for constructing equivariant fibrations
Obstructions to the existence of fold maps
Obtaining intermediate rings of a local profinite Galois extension without localization
Odd-primary homotopy exponents of compact simple Lie groups
On "small geodesics" and free loop spaces
On (Enriched) Left Bousfield Localization of Model Categories
On 2-dimensional topological field theories
On 2-Holonomy
On a conjecture of Daniel H. Gottlieb
On a Generalization of the Notion of Semidirect Product of Groups
On a Morelli type expression of cohomology classes of toric varieties
On a notion of maps between orbifolds, II. homotopy and CW-complex
On a spectral sequence for twisted cohomologies
On a theorem of Eilenberg in simplicial Bredon-Illman cohomology with local coefficients
On adic genus, Postnikov conjugates, and lambda-rings
On Alexander modules and Blanchfield forms of null-homologous knots in rational homology spheres
On almost free torus actions and Horrocks conjecture