Update activation_time_distribution_measurement.md

Author: TorkelE

docs/src/model_simulation/examples/activation_time_distribution_measurement.md

@@ -45,7 +45,7 @@ eprob = EnsembleProblem(sprob; output_func, safetycopy = true)
 esol = solve(eprob, ImplicitEM(); trajectories = 250, callback)
 nothing # hide
 ```
-Finally, we can plot the distribution of activation times. For this, we will use the [`histogram`](@ref https://docs.juliaplots.org/latest/series_types/histogram/) function (with the `normalize = true` argument to create a probability density function). An alternative we also recommend is [StatsPlots.jl](https://docs.juliaplots.org/latest/generated/statsplots/)'s `density` function (which creates a smoothed histogram that is also easier to combine with other plots). The input to `density` is the activation times (which our output function has saved to `esol.u`).
+Finally, we can plot the distribution of activation times. For this, we will use the [`histogram`](https://docs.juliaplots.org/latest/series_types/histogram/) function (with the `normalize = true` argument to create a probability density function). An alternative we also recommend is [StatsPlots.jl](https://docs.juliaplots.org/latest/generated/statsplots/)'s `density` function (which creates a smoothed histogram that is also easier to combine with other plots). The input to `density` is the activation times (which our output function has saved to `esol.u`).
 ```@example activation_time_distribution_measurement
 histogram(esol.u; normalize = true, label = "Activation time distribution", xlabel = "Activation time")
 ```
@@ -54,4 +54,4 @@ Here we that the activation times take some form of long tail distribution (for
 ---
 ## References
 [^1]: [David Frigola, Laura Casanellas, José M. Sancho, Marta Ibañes, *Asymmetric Stochastic Switching Driven by Intrinsic Molecular Noise*, PLoS One (2012).](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0031407)
-[^2]: [Christian P Schwall et al., *Tunable phenotypic variability through an autoregulatory alternative sigma factor circuit*, Molecular Systems Biology (2021).](https://www.embopress.org/doi/full/10.15252/msb.20209832)
+[^2]: [Christian P Schwall et al., *Tunable phenotypic variability through an autoregulatory alternative sigma factor circuit*, Molecular Systems Biology (2021).](https://www.embopress.org/doi/full/10.15252/msb.20209832)