@testset "6.5 Hyperbolic secant" begin
    include("6.5.1 (c+d x)^m (a+b sech)^n.jl")
    include("6.5.2 (e x)^m (a+b sech(c+d x^n))^p.jl")
    include("6.5.3 Hyperbolic secant functions.jl")
    include("6.5.7 (d hyper)^m (a+b (c sech)^n)^p.jl")
end
