“…An alternative characterization is that X is a prequojection if and only if X has no nuclear quotient which admits a continuous norm, see [5,14,33,37]. The problem of the existence of non-trivial prequojections arose in a natural way in [5]; it has been solved, in the positive sense, in various papers, [6,14,32]. All of these papers employ the same method, which consists in the construction of the dual of a prequojection, rather than the prequojection itself, which is often difficult to describe (see the survey paper [29] for further information).…”