I have observed that Dutch scholars writing articles in English often use "belong with" in the sense of "belong to". Could you tell me is it correct, and if it is, what is the difference between the two expressions? Is it an accident that the variant "belong with" is so popular in the Dutch tradition, or this featuture can also be explained?

Many thanks!
This sounds like a question for AnnVan!
1. That cup belongs with this saucer.

— the two items form a set.

2. That cup belongs to me.

— that cup is my possession.

(I'll leave the Dutch part too.)

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A good explanation from MrPedantic!
As for the Dutch bit...
"toebehoren", "behoren" and "horen bij" can be translated "belong to".

"Belong with", meaning "be part of" ("onderdeel uitmaken van") can be translated "(be)horen bij", e.g....

"Die tafel behoort bij deze stoelen." = "That table belongs with (or "goes with") these chairs."

"Het hoort bij de anderen." = "It belongs with the others."

... Certainly potential for confusion, but why the Dutch might prefer "belong with" even when "belong to" is necessary - I'm not sure. (My Dutch husband got it right when I gave him a 'spontaneous test', so he's no help, haha!)
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