Let's Gather Gathas! (& how-to)

[Meian]

hello,

i did try researching this topic on my own -- in the forums and via search engines.

i found links and posts with written gathas and member-submitted gathas, and articles about gathas by famous Zen monks.

i have not found any resources about how to create a gatha, other than it has four lines (according to one website).

but four lines of what? what is a gatha comprised of?

Haiku has certain rules that must be followed. do gathas have rules also? a certain format?

please forgive if i am over-thinking this (probably). but with rohatsu, i saw the additional verses and gathas, and became very interested in learning how to write more.

any resources or guidance would be most appreciated. perhaps i just don't know the correct search terms.

gassho
kim
st lh