How many authors does the publication 'Directivity in RF Sensor Networks for Widespread Spectrum Monitoring' have?
Mention the number of authors of the paper 'Directivity in RF Sensor Networks for Widespread Spectrum Monitoring'.
SELECT ?answer WHERE { <https://dblp.org/rec/journals/tccn/KleberHCHL22> <https://dblp.org/rdf/schema#numberOfCreators> ?answer }
<https://dblp.org/rec/journals/tccn/KleberHCHL22>