Here are some links I have found useful while researching Mauirico Berger and his fraudulent sealed portion from the gold plates. The first two articles are ones I wrote myself.
Evidence That Mauricio Berger’s “Golden Plates” Were Fabricated
Response to the Brazilian Testimonies By the Quorum of Restoration Apostles (backup)
This last link is for a list of scriptures in the Book of Ether I put together for a friend regarding the sealed portion because she was reading the Mentinah Archives and things she was stating it taught about the Sealed Portion was in contradiction to what was being said in the Book of Mormon about it.
Here are some interesting article on the Brazil faction.
Here are links to buy or download the supposed Sealed Book of Mormon