That's indeed a good article on resistant starch. I have no issues with it.

As natural sources, with a relatively high content of resistant starch (≥5 gram / 100 gram), you may choose plantain, whole rolled oats, semolina, corn flaked, whole grain rye bread, corn tortilla, lima and black beans, some potato types. Surprisingly, also the cooking method can increase the content of resistant starch. If you fry rice and then chill it, it will increase its content of indigestible (resistant) starch considerably.