finding implicits in scala libraries

Question

I have a list as below

    val S = Interval.open(1.0, 4.5)
    val A = Interval.open(1.0, 3.0)
    val B = Interval.open(2.0, 4.0)
    val C = Interval.openUpper(3.0, 4.5)
    val list = (S \ A).union(S \ B)
    println(list)

List([3.0, 4.5), (1.0, 2.0], [4.0, 4.5))

and I want to sort it.

 println(list.sorted)

But is giving the error as below

Error:(18, 18) No implicit Ordering defined for spire.math.Interval[Double].
    println(list.sorted)(Ordering)

But I'm not sure where that implicit be available.

1. where that implicit might have declared.

How to find in library where that implicit is available ?