1. Yu. M. Shirokov, ?Strongly singular potentials in three-dimensional quantum mechanics,? Teor. Mat. Fiz.,42, 45 (1980).
2. Yu. M. Shirokov, ?Algebra of one-dimensional generalized functions,? Teor. Mat. Fiz.,39, 291 (1979).
3. Yu. M. Shirokov, ?Algebra of three-dimensional generalized functions,? Teor. Mat. Fiz.,40, 348 (1979).
4. M. I. Shirokov, ?Minimally nonlocal quantum electrodynamics of bound electrons without potentials,? Preprint R4-12632 [in Russian], JINR, Dubna (1980).