An extended inhomogeneous minimum

E. S. Barnes
1976 Journal of the Australian Mathematical Society  
A new arithmetic invariant E(f) is defined for integral binary quadratic forms /. It has the property that, denoting by f m the norm-form of a quadratic number field Q(\/m), £(/")< 1 if and only if Q(\/m) has class number one.
doi:10.1017/s1446788700016281 fatcat:u2p3wd3fzfhfdhyfy2l25q4zb4