Technological transfer can be hard to prove unless there is some high-status person doing it and having it documented as part of the process.

Read a paper in history of technology that argued that pre-Gutenberg printing was established in Arab lands independent of Chinese printing. This was shown in part by way of the low status of Arab printing, imported habits from China in general having high status. But because of the low status, it is rarely mentioned - I think there was a quote on whores, thieves and book-printers in the paper - meaning the amount of evidence is small. The author in the end argue that it is possible that printing moved with printers into Italy, where they for lack of local language focused on printing pictures, like Tarot cards. And that way it can have spread to Germany.

Arab printing was apparently out-competed by the more high-status habit of writing.

Sweden's finest (and perhaps only) collaborative, leftist e-newspaper Synapze.se

It's an oblique reference, but David Graeber in Debt: The First 5,000 Years corroborate on this: the cultural supremacy and influence of the Far East, and the Muslim civilisation; the Muslim practice to separate trade and war (whereas Europeans invariably mingled the two; he state that before the European expansion the Indian ocean was a war free trade zone); also in Debt Graeber develop the thesis that the European expansion, and the savagery it entailed, was driven not because the Muslin conquests had cut the trade with the Far East, but for the reasons of extreme and violent commercialisation of European societies which resulted many were hopelessly in debt, and as consequence capable of absolutely anything.