I was looking at Arya Samaj’s translation of Vedas on onlineved.com and found that the Rig Veda is missing Mandala 7-10. Why is that? Also the way they cite the verses is quite different than the traditional method.
It's available as book. You can read this online. They mentioned Mandala, Sukta on the above of the page
Here you can find whole rig veda of translated by arya samaj. Arya samaj believes that vedas is scientific document and doesn't have any geography or history .example in nadi suktam , arya samaj claims they are not rivers rather they are arteries. That's why their commentary is different from traditional though they claim their commentary is based on yaska and dayanand saraswati