Mba, Ifeoma Christy, et al. “Mean Sojourn and Mean Return Time of the Buy-Hoard-Sell Strategy of Bitcoin Exchange Prices”. International Journal of Economics and Financial Issues, vol. 8, no. 5, Sept. 2018, pp. 276-82, https://econjournals.com.tr/index.php/ijefi/article/view/6777.