Just guessing....

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Note added at 55 mins (2017-01-17 17:47:29 GMT)
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http://www.linguee.es/espanol-ingles/search?source=auto&quer...

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Note added at 17 hrs (2017-01-18 10:24:54 GMT)
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PS: In this case, I understand "mayorista" to mean the opposite of specialist". Otherwise, perhaps the use of "cátedra"is idiosyncratic or regional?

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Note added at 17 hrs (2017-01-18 10:28:09 GMT)
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If that's not floating your boat, how about "wholesale management course" then?
http://www.worldcat.org/title/summaries-of-wholesaling-lectu...

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Note added at 17 hrs (2017-01-18 10:31:07 GMT)
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DRAE: cátedra -> Facultad o materia particular que enseña un catedrático. I.e. a course or subject. So it is more likely to be a course in wholesale management studies for would-be wholesalers, not aspiring professors.

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Note added at 17 hrs (2017-01-18 10:32:27 GMT)
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Here's one called a "wholesale masterclass":

http://www.emergents.co.uk/project/growing-in-confidence/

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Note added at 23 hrs (2017-01-18 16:09:52 GMT)
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For example, a study course like this one:
Tourism Technology: Travel wholesale management system
https://opus.lib.uts.edu.au/handle/10453/12489