2017, Volume 81, Issue 4

This issue is dedicated to the 80th anniversary of the journal

	Topology, singularities and integrability in Hamiltonian systems with two degrees of freedom S. V. Bolotin, V. V. Kozlov Izvestiya: Mathematics, 2017, Volume 81, Issue 4, Pages 671–687 DOI: https://doi.org/10.1070/IM8600 Izvestiya Rossiiskoi Akademii Nauk. Seriya Matematicheskaya, 2017, Volume 81, Issue 4, Pages 3–19 DOI: https://doi.org/10.4213/im8600		671–687
	Integrable topological billiards and equivalent dynamical systems V. V. Vedyushkina (Fokicheva), A. T. Fomenko Izvestiya: Mathematics, 2017, Volume 81, Issue 4, Pages 688–733 DOI: https://doi.org/10.1070/IM8602 Izvestiya Rossiiskoi Akademii Nauk. Seriya Matematicheskaya, 2017, Volume 81, Issue 4, Pages 20–67 DOI: https://doi.org/10.4213/im8602		688–733
	Universal adic approximation, invariant measures and scaled entropy A. M. Vershik, P. B. Zatitskii Izvestiya: Mathematics, 2017, Volume 81, Issue 4, Pages 734–770 DOI: https://doi.org/10.1070/IM8610 Izvestiya Rossiiskoi Akademii Nauk. Seriya Matematicheskaya, 2017, Volume 81, Issue 4, Pages 68–107 DOI: https://doi.org/10.4213/im8610		734–770
	Many-circuit canard trajectories and their applications S. D. Glyzin, A. Yu. Kolesov, N. Kh. Rozov Izvestiya: Mathematics, 2017, Volume 81, Issue 4, Pages 771–817 DOI: https://doi.org/10.1070/IM8547 Izvestiya Rossiiskoi Akademii Nauk. Seriya Matematicheskaya, 2017, Volume 81, Issue 4, Pages 108–157 DOI: https://doi.org/10.4213/im8547		771–817
	Grothendieck–Verdier duality patterns in quantum algebra Yu. I. Manin Izvestiya: Mathematics, 2017, Volume 81, Issue 4, Pages 818–826 DOI: https://doi.org/10.1070/IM8620 Izvestiya Rossiiskoi Akademii Nauk. Seriya Matematicheskaya, 2017, Volume 81, Issue 4, Pages 158–166 DOI: https://doi.org/10.4213/im8620		818–826
	A criterion for semiampleness V. V. Shokurov Izvestiya: Mathematics, 2017, Volume 81, Issue 4, Pages 827–887 DOI: https://doi.org/10.1070/IM8438 Izvestiya Rossiiskoi Akademii Nauk. Seriya Matematicheskaya, 2017, Volume 81, Issue 4, Pages 167–230 DOI: https://doi.org/10.4213/im8438		827–887