I am trying to decide whether the Wolfram Knowledgebase can be useful to me in the classroom. For this to be the case, I need to easily determine the source of the data and its units. I'll give two examples.
As a very simple example, pop=EntityProperty["Country", "Population"] allows source retrieval as pop["Source"]. (Note however that EntityProperty["Country", "Population", {"Date" -> DateObject[{2016}]}] is oddly unable to retrieve its source.) Anyway, the source is Entity["Source", "UNData"], which provides a link to http://data.un.org/ and a reference to the United Nations Statistics Division. To be useful, I need access to enough detail to reproduce the number. Is more detail available?
As a slightly more complex example, suppose we consider the country GDP entity, whose documentation points us to the World Development indicators at http://data.worldbank.org/data-catalog/world-development-indicators. But even setting aside the failure to reference a particular release of the WDI, the idea of reporting GDP of other countries in dollars is not simple, and the WDI includes multiple versions. An obvious solution would be to provide the series identifier in a note, but the note is empty. Does it exist elsewhere? (To be clear, the question is NOT whether in this particular case one can look at the underlying data and guess which series is being used; it is rather whether the documentation exists somewhere accessible in the Wolfram Knowledgebase.)
