How to print to \score { } constructs next to each other instead of underneath

[James Lowe]

Hello

A simple example

---

\version "2.13.40"

top = \relative c'' {
\clef "treble"
a b c d
}

bottom = \relative c {
\clef "bass"
a b c d
}

\score {
<<
\new Staff { \top }
\new Staff { \bottom }
>>
}

\score {
<<
\new Staff { \top }
\new Staff { \bottom }
>>
}

\score {
<<
\new Staff { \top }
\new Staff { \bottom }
>>
}

---

This prints 3 grouped staves underneath each other, how would one go about 
getting them so the three scores are running left to right instead?

I have tried things like

\score {
<<
\new Staff { \top \stopStaff s1 \startStaff \top \stopStaff s1 \startStaff \top 
\stopStaff s1 \startStaff \top }
\new Staff { \bottom \stopStaff s1 \startStaff \bottom \stopStaff s1 
\startStaff \bottom }
>>
}

But I have to then fiddle with 'forceClef' and 'full size clef' and even then 
the clef is behind the barline that gets printed, I could then remove that bar 
line manually but then it starts to get a bit complicated. So I just wondered 
if there was a way to tell LP to print a new \score to the right instead of 
underneath the one before it?

Thanks as usual for your time.

James