We study P-critical edge-bipartite graphs (bigraphs for short) aDelta; with n age; 2 vertices, by means of the non-symmetric Gram matrix aG?aDelta; aepsi; aMopf;n(aZopf;), the Coxeter matrix CoxaDelta; := - aG?aDelta; amiddot; aG?aDelta;-tr aepsi; aMopf;n(aZopf;), its Coxeter polynomial coxaDelta;(t)=det (tamiddot; E+aG?aDelta;amiddot; aG?aDelta;-tr), and its Coxeter spectrum speccaDelta;. We recall that aDelta; is positive if the symmetric matrix GaDelta; := aG?aDelta;+aG?aDelta;tr is positive definite, and aDelta; is P-critical if it is not positive and each of its proper full subbigraphs is positive. It is easy to see that if two bigraphs aDelta;, aDelta;aprime; are aZopf;-bilinear equivalent aDelta;aasymp;asopf; aDelta;aprime; (i.e., there exists a matrix B aepsi; Gl (n,aZopf;) such that aG?aDelta;=Btramiddot; aG?aDelta;aprime;amiddot; B) then their Coxeter spectra speccaDelta; and speccaDelta;aprime; coincide, but the converse implication does not hold in general. One of the main questions of the Coxeter spectral analysis of connected P-critical bigraphs aDelta;, aDelta;aprime; is whether the congruence aDelta;aasymp;asopf;aDelta;aprime; holds if and only if speccaDelta; = speccaDelta;aprime;. In this note we discuss the problem in case when n ale; 10 and aDelta; and aDelta;aprime; are P-critical loop-free bigraphs such that their Euclidean types DaDelta;, DaDelta;aprime;aepsi; aAopf;n, n age; 1, aDopf;m,m age; 4, aEopf;6, aEopf;7, aEopf;8 coincide. We also extend our results proved earlier (see MPS-PoSim2012). In particular, we get an affirmative answer to the stated question, for a large class of P-critical bigraphs and Tits P-critical finite posets. By applying symbolic and numerical algorithms in Maple and C# we compute the set of Coxeter polynomials coxaDelta;(t) for P-critical loop-free bigraphs aDelta;, with at most 10 vertices.