Thanks to this package by ljo, you can enter here your SPARQL query to the RDF representation of the data. PLEASE use single quotes ' not double.
PREFIXes are already there (see below), so you can start with SELECT. If you prefer to use your prefixes, do so, no problem. A super tutorial on how to build SPARQL queries is here at Apache Jena
You can also use the API to query the SPARQL endpoint, using https://betamasaheft.eu/api/SPARQL with the query in a parameter q. The results are SPARQL Query Results XML Format, as the one visualized below.
In the Beta maṣāḥǝft Guidelines you can find the OWLDoc Documentation and a visualization thanks to webVOWL of the current ontology developed with Protégé.
Some examples of the data you are querying
Documentation on Linked Open Data can be found here.
The results presented here are visualized with d3sparql