We extend the theory of tax incidence under Cournot-Nash oligopolistic competition to study the effects of an ad valorem sales tax on Web services (so-called Web Tax) that are provided free of charge to users, and produce advertising space sold to businesses. Ads are more valuable to advertisers...

Governments intervene in non-renewable natural resources sectors more than in many others, including through the use of export taxes and quotas. Industrial raw materials sectors are characterized by a number of specificities: production is often geographically concentrated, firms are often large...