Newbie question on has_may : through and link_to

Ok. This is a stupid newbie question.

We have a database which has tables of topics, countries, countrynotes and countrynotes_topics (Any countrynote can relate to multiple topics and any topic can relate to multiple country notes, each countrynote can relate to only one country). What I want to do is when I show the index of topics, each topic will have a link_to that will generate a index page of the countrynotes related to that topic. Similarly, an index page of countries should have a link_to which will generate an index of topics related to that country and a link_to which will generate an index of countrynotes related to that country. I have no problem doing this the hard way through straight sql statements (that is how the program works today [in a different language]). The question is what is the best RESTful way to build the link_to in Rails?

class Topic < ActiveRecord::Base has_many :countrynotes, :through => :countrynotes_topics has_many :countrynotes_topics end

class Countrynote < ActiveRecord::Base belongs_to :country has_many :countrynotes_topics has_many :topics, :through => :countrynotes_topics end

class CountrynoteTopic < ActiveRecord::Base belongs_to :countrynote belongs_to :topic end