Shiva Purana
तृणपर्णैः सदा कुर्यादमामेकादशी विना ॥ अपां द्वादशगण्डूषैर्मुखं संशोधयेत्ततः ॥ १३ ॥
One should always perform this ritual with grass and leaves except on Ekadashi Then cleanse the face with twelve drops of water.
english translation
tRNaparNaiH sadA kuryAdamAmekAdazI vinA ॥ apAM dvAdazagaNDUSairmukhaM saMzodhayettataH ॥ 13 ॥
hk transliteration by Sanscript