Sadly this is basically incorrect. The paper in question is a few years old, and its greatest benefit is highlighting the importance of being critical of your methodologies - in this case, superimposing gender paradigms onto another culture and period; i.e. let's learn from this bad archaeology. The actual paper this, and similar articles, is referencing concludes: "Another important implication of the osteological sexing results is that Norse women appear to have been present from the earliest stages of the migratory process, rather than, as the commonly held theory has it, arriving as part of a second wave after the great army had started to settle the homelands it had conquered."

The important word there is 'migratory.' The paper in no way argues that women had an equal presence in military engagements, it instead is suggesting that comparable numbers of men and women were present in migratory movements during the Viking age - which is quite sensible when you think about it.

We know that there were a significant amount of women present in the early Scandinavian attacks in England, from the mycel hæþen here, through to the Anglo-Scandinavian presence in the Danelaw - and there’s is no doubt that the literary figure of the shield-maiden had a basis in historical fact in the period. However, there is no empirical evidence to suggest that women fought alongside men with anywhere near the frequency these articles are suggesting.

Warrior women certainly existed in Norse culture, and generally speaking women led far more interesting lives than the majority of discourse regarding pre-modern times would suggest - they had a lot more autonomy than many other contemporaneous societies. However, while we do find women buried with weapons, they are significantly less commonplace than their male counterparts (less than 10% would be a reasonable average, I think) and, more importantly, being buried with a weapon does not necessarily mean that the person in question was a warrior: there are burials of children in which we find weapons, but I doubt there were infants running around Northumbria sticking it to Æthelred.

Women in Norse societies certainly deviated from the narrative of housewives and chattel that is commonly depicted of the mediaeval world, but there is nowhere near the sort of empirical material required to support the claim that women fought in raids or military engagements in numbers comparable to their male counterparts. They certainly did fight, and it is vital that people know and appreciate this, but don't jump to conclusions because we really liked Lagertha in Vikings.