<s>
ALGOL	B-Language
X	I-Language
was	O
the	O
code	O
name	O
given	O
to	O
a	O
programming	O
language	O
which	O
was	O
being	O
developed	O
as	O
a	O
successor	O
to	O
ALGOL	B-Language
60	I-Language
,	O
by	O
the	O
International	O
Federation	O
for	O
Information	O
Processing	O
(	O
IFIP	O
)	O
IFIP	B-Language
Working	I-Language
Group	I-Language
2.1	I-Language
on	O
Algorithmic	B-Language
Languages	I-Language
and	O
Calculi	O
,	O
which	O
supports	O
and	O
maintains	O
the	O
languages	O
ALGOL	B-Language
60	I-Language
and	O
ALGOL	B-Language
68	I-Language
.	O
</s>
<s>
ALGOL	B-Language
N	I-Language
and	O
ALGOL	B-Language
W	I-Language
were	O
two	O
other	O
ALGOL	B-Language
versions	O
proposed	O
to	O
fulfill	O
this	O
need	O
.	O
</s>
<s>
According	O
to	O
de	O
Morgan	O
,	O
"	O
...	O
the	O
Algol	B-Language
60	I-Language
devotees	O
had	O
not	O
been	O
idle	O
...	O
they	O
set	O
out	O
to	O
eliminate	O
the	O
dreaded	O
Remaining	O
Trouble	O
Spots	O
.	O
</s>
<s>
They	O
called	O
their	O
Algol	B-Language
60	I-Language
'	O
Modified	O
 '	O
.	O
"	O
</s>
<s>
One	O
ALGOL	B-Language
X	I-Language
compiler	O
is	O
known	O
to	O
have	O
existed	O
.	O
</s>
<s>
It	O
was	O
written	O
with	O
the	O
Automated	O
Engineering	O
Design	O
(	O
AED-0	O
)	O
system	O
,	O
also	O
termed	O
ALGOL	B-Language
Extended	O
for	O
Design	O
,	O
by	O
Douglas	O
T	O
.	O
Ross	O
of	O
the	O
Massachusetts	O
Institute	O
of	O
Technology	O
(	O
MIT	O
)	O
.	O
</s>
