“…If that fixed vertex is chosen to be the tiling shown in Fig. 8 (n=5), then the poset we obtain is the higher Bruhat order B(n, 2), described in [10] and [16] .., [a 1 + } } } +a m&1 +1, ..., n], while preserving the consecutiveness and the order of the elements within each block. Then _ can be thought of as a (special kind of) permutation of a multiset with a i copies of i, for i=1, ..., m. Since the different copies of the same i are not permuted among themselves, we can make the edges corresponding to them parallel.…”