„The Henley Passport Index“. Henley & Partners Holdings Ltd (2021-yil 5-yanvar). — „This graph shows the full Global Ranking of the 2021 Henley Passport Index. In certain cases, a rank is shared by multiple countries because these countries all have the same level of visa-free or visa-on-arrival access.“. Qaraldi: 2021-yil 5-yanvar.
