A ring-like accretion structure in M87 connecting its black hole and jet
R.-S.L., K. Asada, T.P.K. and K.H. initiated the project and coordinated the research. P.H., M.I., M.-T.C., S.M., K. Asada, P.M.K., Y.-D.H., C.-C.H., D.K., P.A.R., T.J.N., N.A.P. and other engineers and technicians in East Asia made the GLT available for our observations. K. Asada, T.P.K., R.-S.L., I.M.-V., J.P. and E.R. worked on the VLBI scheduling and coordination of the observations, analysis and calibration of the data. K. Akiyama, K. Asada, K.H., J.-Y. Kim, T.P.K., R.-S.L., J.P., F.T. and A.L. worked on image reconstruction and model fitting. K. Asada, J.L.G., K.H., J.-Y. Kim, T.P.K., T.K., A.L., R.-S.L., M.N., J.P., H.-Y.P. and F.Y. worked on the scientific interpretation of the results. All authors approved the paper and contributed to writing the observing proposal, carried out the observations, produced and/or applied software tools for analysis and interpretation, and contributed to the general interpretation of the data.