Toward estimation of H0 from VLBI observations of the gravitational lens system 0957+561

1. Campbell, R.M.
2. Corey, B.E.
3. Falco, E.E.
4. Shapiro, I.I.
5. Gorenstein, M.V.
6. Elósegui, P.
7. Marcaide, J.M.
8. Alvi, K.