“…It is well-known [31] that the small Seifert fibred 3-manifold Y = Y (e 0 ; r 1 , r 2 , r 3 ) can also be described by a star-shaped weighted plumbing tree, where the central vertex has weight e 0 and there are three legs emanating from that vertex corresponding to the continued fraction expansions of the rational numbers − 1 r i , for i = 1, 2, 3, respectively. If e 0 ≤ −3, then we can easily identify ξ can on Y , based on the work in [13,32,38] (see Section 6).…”