. D ias , ▁G . I o oss . ▁Water - w aves ▁as ▁a ▁spatial ▁dynam ical ▁system . ▁Hand book ▁of ▁Mathemat ical ▁Fl uid ▁Dynam ics , ▁chapter ▁ 1 0 , ▁ 4 4 3 - 4 9 9 . ▁S . F ried land er , ▁D . Ser re , ▁ed s ., ▁Else vier . ▁ 2 0 0 5 ▁G . I o oss , ▁P . Plot nik ov , ▁J . F . T ol and ▁.   ▁Stand ing ▁waves ▁on ▁an ▁infinitely ▁deep ▁perfect ▁fluid ▁under ▁gravity . ▁Arch . ▁Rat . ▁Me ch . ▁Anal . ▁ 1 7 7 , ▁ 3 , ▁ 3 6 7 - 4 7 8 . ▁▁ 2 0 0 5 ▁G . I o oss , ▁E . L omb ardi . ▁Pol ynomial ▁normal ▁forms ▁with ▁expon entially ▁small ▁remainder ▁for ▁analyt ical ▁vector ▁fields . ▁J . Diff . ▁Equ . ▁ 2 1 2 , ▁ 1 - 6 1 . ▁▁ 2 0 1 1 ▁G . I o oss , ▁P . Plot nik ov . ▁As ym met rical ▁three - dimensional ▁trav elling ▁gravity ▁waves . ▁( 9 1 p .) ▁Arch . ▁Rat . ▁Me ch . ▁Anal . ▁ 2 0 0 , ▁ 3 ▁( 2 0 1 1 ), ▁ 7 8 9 - 8 8 0 . ▁▁ 2 0 1 9 ▁B . Bra aks ma , ▁G