MLA

Mexico. Laws, statutes, etc. 1830, April 6. [Decree of the Congreso General, approved by Vice-President Anastasio Bustamente on April 6, 1830, and promulgated the same day by Lucas Alaman, relating to colonization. 1830]. https://collections.library.yale.edu/catalog/2007280.

APA, 6th edition

Mexico. Laws, statutes, etc. 1830, April 6. (1830])[[Decree of the Congreso General, approved by Vice-President Anastasio Bustamente on April 6, 1830, and promulgated the same day by Lucas Alaman, relating to colonization]. https://collections.library.yale.edu/catalog/2007280.