pg with different sql?

Hi all,

I'm new to postgres and I'm doing a database project for a
subject at college in postgres. I've studied databases using
DataBases Management Systems by Ramakrishnan.
I've done some create tables and at psql interactive prompt I've
done:
\i proj.sql
(where proj.sql is the filename with the CREATE TABLEs)

AFAIK, SQL is standard and should be the same for all DBMSs.

For example:
CREATE TABLE socio (
id integer SERIAL PRIMARY KEY,
nome varchar,
alcunha string,
data_filiacao date)

CREATE TABLE paga_cota (
ano integer,
mes integer,
valor integer,
id integer,
PRIMARY KEY(id,ano,mes),
FOREIGN KEY(id) REFERENCES(socio))

After this I get an error around CREATE (of the 2nd table). I
just can't imagine what it might be.

I'd appreciate your help.

TIA,
My best regards,
--
Paulo J. Matos : pocm(_at_)rnl.ist.utl.pt
Instituto Superior Tecnico - Lisbon
Software & Computer Engineering - A.I.
- > http://www.rnl.ist.utl.pt/~pocm
---
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