I believe all his notable scientific works were in English. You can find some minor articles in Danish, e.g. this announcement of the RC4000 in an engineering p

I believe all his notable scientific works were in English. You can find some minor articles in Danish, e.g. this announcement of the RC4000 in an engineering periodical: https://datamuseum.dk/w/images/d/da/Rc4000d.pdf https://datamuseum.dk/w/images/d/da/Rc4000d.pdf