9 citations · 20 across the 5 of their papers we have counts for
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Birational automorphisms of nodal quartic threefolds
Constantin Shramov
It is well-known that a nonsingular minimal cubic surface is birationally rigid; the group of its birational selfmaps is generated by biregular selfmaps and birational involutions…
On rationality of nonsingular threefolds with a pencil of Del Pezzo surfaces of degree 4
Constantin Shramov
We prove a criterion of nonsingularity of a complete intersection of two fiberwise quadrics in a scroll over . As a corollary we derive the following addition to the Alexeev t…
Birational rigidity and Q-factoriality of a singular double quadric
Constantin Shramov
We prove birational rigidity and calculate the group of birational automorphisms of a nodal Q-factorial double cover of a smooth three-dimensional quadric branched over a quart…
Q-factorial quartic threefolds
Constantin Shramov
We prove that a nodal quartic threefold containing no planes is -factorial provided that it has not more than 12 singular points, with the exception of a quartic with exactl…
Hyperelliptic and trigonal Fano threefolds
Ivan Cheltsov, Constantin Shramov, Victor Przyjalkowski
We classify Fano 3-folds with canonical Gorenstein singularities whose anticanonical linear system has no base points but does not give an embedding, and we classify anticanonicall…