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2. B. Sawe, “Top 10 rice consuming countries,” https://www.worldatlas.com/articles/top-10-rice-consuming-counties.html (2019).
3. D. Mapa, “Palay and corn quartely bulletin,” https://psa.gov.ph/sites/default/files/Palay (2021).
4. “Topography,” https://cagayano.tripod.com/geotopo.html#:∼:text=Cagayan%20is%20a%20vast%20expanse,area%20of%20about%2027%2C300%20sq.
5. “Cagayan valley remains number 1 corn producer, 2nd in rice,” Regional Development Council Cagayan Valley Region (2022).