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function RKF45{T<:Float64}(f, g, h, t0, tf, v0::T, w0::T)
    # Initial values
    t = t0
    v5 = v4 = v = v0
    w = w0

    tolerance = 10^(-5.0)

    # Create list for future plots
    t_list = [t]
    v_list = [v]
    w_list = [w]

    # Values for a, b and c (as on Butcher's tableau)
    a = [    0          0           0          0        0    0;
         1/4         0           0          0        0    0;
         3/32       9/32         0          0        0    0;
         1932/2197 -7200/2197   7296/2197      0        0    0;
         439/216      -8       3680/513   -845/4104    0    0;
         -8/27        2      -3544/2565  1859/4104 -11/40  0]

    b = [16/135  0   6656/12825  28561/56430  -9/50  2/55;
         25/216  0   1408/2565   2197/4104     -1/5   0]

    c = [0 1/4 3/8 12/13 1 1/2]

    # Relative to y
    k = Float64[0 0 0 0 0 0]

    # Relative to z
    l = Float64[0 0 0 0 0 0]

    # Compute the next terms
    for i in t0:h:tf
        # Compute the next values of K and L
        for j in 1:6
            k[j] = f(t + c[j] * h, v + (a[j,:] * k')[1], w + (a[j,:] * l')[1])*h
            l[j] = g(t + c[j] * h, v + (a[j,:] * k')[1], w + (a[j,:] * l')[1])*h
        end


        ############################################################################
        # Compute the next value of V                                              #
        # Here we implemented a tolerance test                                     #
        ############################################################################
        v4 = v + (b[2] * k')[1]                                                       #
        v5 = v + (b[1] * k')[1]                                                       #
        #
        error = abs(v5 - v4)                                                       #
        if error > tolerance                                                       #
            #
            h = 0.9 * h * ((tolerance/error) ^ (0.25))                             #
            #
            for j in 1:6                                                           #
                k[j] = f(t + c[j] * h, v + (a[j] * k')[1], w + (a[j] * l')[1])*h   #
                l[j] = g(t + c[j] * h, v + (a[j] * k')[1], w + (a[j] * l')[1])*h   #
            end                                                                    #
            #
            v5 = v + (b[1,:] * k')[1]                                              #
        end                                                                        #
        #
        v = v5                                                                     #
        ############################################################################

        # Compute T and W with the right values of H and L, obtained after the tolerance test
        t += h
        w += (b[1,:] * l')[1]

        # Append new values to the lists
        push!(t_list,t)
        push!(v_list,v)
        push!(w_list,w)
    end

    return t_list, v_list, w_list
end

function f(t, v, w)
        return (v*(v-a)*(1-v) - w + I)/ε
    end

function g(t, v, w)
        return (v - p*w - b)
    end

ε = 0.005
a = 0.5
b = 0.15
p = 1.0
I = 0.0
h = 0.005

# Initial and final values of time
t0 =  0.0
tf =  8