Sometimes, you can judge how reliable website information is by noting the URL ending.
.GOV - refers to a government website. Highly reliable.
.EDU - often refers to a reliable educational website.
.ORG - implies a non-profit ORGanization. Approach with skepticism.
.COM - stands for "Commerce" and is used for business. Information on such a website will contain a large amount of bias. Approach with skepticism.
CIA World Fact Book - Authoritative overviews of country data.
Freedomhouse.org - press and media freedom rankings across the globe.
Statistics from the International Telecommunication Union
Links to national organizations providing statistics on telecommunication. Links compiled by the International Telecommunication Union.
UN Data - World Telecommunication/ICT Indicators Database, IT
The Constitute Project- even if the "comparator" function does not work, you can simply look up constitutions and do your own side-by-side analyses.
Nigeria --> Media in Nigeria
Identify government, academic publisher, and official country sources.
Locate those sources. If you can't access or get it, you can't really know what it contains or how it is relevant to your project.
If the library doesn't have it, use Interlibrary Loan.