D. Fradkin

Expectation values of descendent fields in the sine-Gordon model

V. Fateev, S. Lukyanov, A. Zamolodchikov, 1999 .

Integral expressions for arbitrary phase shift differences

F. Calogero, D. Fradkin, 1966 .

Integral expressions for the difference between contiguous Dirac phase shifts

F. Calogero, D. Fradkin, 1966 .