Subscribe to see new publications and popular science coverage of current research on your homepage
Wait why do they call it a "viking ship", not only it was a cog, type of ship i never heard being connected to vikings but at the point of XV century viking age was long gone, it was the age of Hansa, which notably extensively used cogs - big and heavy ships made for trade.
A cog: 
And apparently it was built in The Netherlands by "viking artisans". I can see how they would deduce where it was built (from material choices?) but how do they know it was specifically built by vikings.
No idea, especially that viking was not even a full time profession, not to mention that it was not an ethnicity. 1410 Dutch shipmakers were most likely experienced guild artisans living in a city and their activities didn't included armed coastal robbery.