“…As P is cofibrant (and any chain operad is fibrant), by the theory of model categories, there exists a weak equivalence q : P → H. We can take a cycle g ′ ∈ P(1) such that the class [g ′ ] goes to β m by p * . The pair (i(ν 1 ), g ′ ) satisfies the condition of Definition 4.1 for P. It is clear that the pairs (ν, p(g ′ )), (q(g ′ ), qi(ν 1 )) also ω(i(ν 1 ), g ′ ) ✤ o o ✤ / / ω(qi(ν 1 ), q(g ′ )) (14) By these isomorphisms, [ω(ν, p(g ′ ))] corresponds to [ω(qi(ν 1 ), q(g ′ ))]. As we show in the above, [ω(ν, p(g ′ ))] is non-zero.…”