The MapBiomas data are public, open and free under Creative Commons CC-BY license and by referencing the source observing the following format:
MapBiomas – Collection [version] of the [annual / monthly] series of Maps of [Land Cover and Use / Fire Scar / Surface Water / Soil Carbon] of Brazil, accessed on [data] through the link: [LINK]“
Additionally, there are Scientific Articles from MapBiomas that can be used for citation.