On Coxeter spectral classification of P-critical edge-bipartite graphs of Euclidean type

We present a complete list of the Coxeter polynomials of P-critical bigraphs Δ, for | Δ 0 | ⩽ 8 . Moreover, given P-critical bigraphs Δ, Δ ′ of the Euclidean type D Δ = A ˜ n − 1 and n ⩽ 8 , we establish by a computer calculation the equivalence of the following three statements: (a) cox Δ ( t ) = cox Δ ′ ( t ) , (b) the reduced Coxeter numbers c Δ and c Δ ′ of Δ and Δ ′ coincide, (c) the tubular types tub Δ and tub Δ ′ of Δ and Δ ′ coincide (see Section 2).