I visited the city archives in Västerås the other day to look for a couple of relatives. They had disappeared without a trace from the house interrogation length with only the comment "Gymnasist" and I suspected they were here. And very true, they studied at Västerås Gymnasium.
The ones I was looking for were the twins Daniel Holm (b. 1751-09-24) and Andreas Holm (b. 1751-09-23) from Hosjö, Vika, Dalarna, and Daniel Åsberg (b. 1754-01-31) from Åsbo , Vika, Dalarna. Also Johan Norstedt (b. 1813-02-15), Höjen, Stora Kopparberg, Dalarna.
I found all four in the archive. Partly in the printed school registers:
https://archive.org/details/rudbeckianska_d1a_vol_1
Partly in handwritten log books:
https://archive.org/details/rudbeckianska_d1b_vol3_4_vasteras_gymnasium_lr
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