GORM中的一对多递归关系

I need to have an Organization which have relation to parent one. Something like this:

type Organization struct {

    gorm.Model

    Parent *Organization `gorm:"ForeignKey:ParentId"`
    Name string `gorm:"size:30"`
    Description string `gorm:"size:100"`
}

I want to have ParentId field which will be referenced to id field in the same table. But as I see there is no field and relation.

How can I fix it ?

I have solved it like this, but I am not sure that it is a correct way:

type Organization struct {

    gorm.Model

    Parent *Organization
    ParentId int `gorm:"TYPE:integer REFERENCES organizations"`
    Name string `gorm:"size:30"`
    Description string `gorm:"size:100"`
}