Is it possible this nested table?

[Quoted] Why there is an error in this sql file when I create the table parameter_values_table?

drop type parameter_type;
drop type value_table;
drop type value_type;
drop table opmode_table;
drop type opmode_type;

create type opmode_type as object(
 name varchar(10));
/

create table opmode_table of opmode_type;

create type value_type as object(
 value number,
 opmode ref opmode_type);
/

create type value_table as table of value_type;
/

create type parameter_type as object(
 name varchar(10));
/

create table parameter_values_table(
parameter parameter_type,
values value_table)
nested table values store as parameter_values;

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Adolfo Sánchez Domínguez   GMV, S.A.  Grupo de Mecánica de Vuelo
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