triplet chord

[Hugh Myers]

Given this:

\version "2.13.7"
upper = {
  e  \times 2/3 { e,8 gis [ b e ] } s4
}

lower = {
  e,,2.
}

{
  \time 3/4
  <<
  \new Staff \relative c'' {
    <<
      \set Score.barNumberVisibility = #all-bar-numbers-visible
      \bar ""
      \override Score.BarNumber #'break-visibility = #'#(#t #t #t)
      \set Score.defaultBarType = "|"
      \new Voice = "1" { \voiceOne \upper }
      \new Voice = "2" { \voiceTwo \lower }
    >>
  }
  \new TabStaff \relative c' {
    <<
      \new TabVoice = "t1" { \voiceOne \upper }
      \new TabVoice = "t2" { \voiceTwo \lower }
    >>
  }
  >>
}

How do I go about achieving a triplet chord--- clearly the above
doesn't, neither does inclusion withing '<' and '>'. Hints?

--hsm