Why is it advisable to eat dried pulses together with cereals?

The proteins in dried pulses have a composition of amino acids that complement those of cereals. With a high content of lysin, but low in methionin and sulphurous amino acids, they provide a harmonious balance with cereals which, on the other hand are low in lysin but not in sulphurous amino acids. The right proportion is 2/3 cereals and 1/3 dried pulses.

Source: IFN