Table:
year
single
peak chart positions
certifications
album

bel
fra
ger
ire
ned
sui
swe
uk
u.s. dance

1996
foxxy
-
-
-
-
-
-
-
-
-
none
1999

1999
25
17
-
14
35
-
52
7
8
none
none

feeling for you
52
72
76
-
57
-
57
16
6
none
none

la mouche
-
-
-
-
-
-
-
53
27
none
none

2002
i'm a woman
55
-
-
-
-
63
-
-
7
none
au reve

the sound of violence
58
-
-
-
29
79
-
49
1
none

2003
thrilla
-
-
-
-
-
-
-
-
-
none

2006
toop toop
52
39
-
-
-
76
-
-
-
none
15 again

2007
rock number one
-
-
-
-
-
-
-
-
-
none

2009
youth, speed, trouble, cigarettes
-
-
-
-
-
-
-
-
-
none
non-album single

2010
"i love you so" (i <3 u so)"
15
47
-
-
-
-
-
52
-
none
the rawkers ep

2016
action
-
-
-
-
-
-
-
-
-
none
ibifornia

the missing
-
121
-
-
-
-
-
-
-
none

"-" denotes releases that did not chart

Statement: in 2006, cassius' single "toop toop" was featured on the album 15 again.
Question: in 2006, which album was cassius' single "toop toop" was featured on?
Answer: 15 again