I'm in process creating new database. I need some help for creating tables.

Following are the requirments:

One Study has many section such as Development.....PreClinic.....And each one of this section has many hanging folder such as Correspondence.....Drug.....Lot.....And each one of the hanging folder has many Sub Hanging Folder and 2nd Sub folder.

I was thinking to create relationship like this :

Study to Section ( 1 to M)
Section to HangingFolder ( 1 to M)
HangingFolder to SubHanging and 2ndSub (1 to M)

But again each section will have hanging folder and subhanging folder.

Any suggestion ?