“…With A = 0, B = 0, and C = 0, Equation ( 3) is the Kortweg de Vries (KDV) and admits symmetric positive definite solitons [4]. Finally, for non-vanishing A, B, C, the BKDV is solved by positive asymmetric solitons [5][6][7][8]. All BKDV soliton-type densities exhibit rapidly decreasing tails and arbitrarily high moments.…”