Set cookies based on referral links

cookies.js

// init namespace
window.app = {};
window.app.custom = {};

(function ($, app) {
  var $window = $(window);

  app.captureCampaign = {
    parameters: ['campaign_source'],
    cookiePersistDays: 30,
    cookiePath: '',
    cookieDomain: "." + window.location.hostname,
    cookieSecure: false,
    getParameterByName: function(name) {
      name = name.replace(/[\[]/, "\\\[").replace(/[\]]/, "\\\]");
      var regexS = "[\\?&]" + name + "=([^&#]*)";
      var regex = new RegExp(regexS);
      var results = regex.exec(window.location.href);
      if (results === null) {
        return "";
      } else {
        return decodeURIComponent(results[1].replace(/\+/g, " "));
      }
    },
    readCookie: function(name) {
      var name = name + "=";
      var cookieArray = document.cookie.split(';');
      for (var i = cookieArray.length - 1; i >= 0; i--) {
        var c = cookieArray[i];
        while (c.charAt(0) === ' ') { c = c.substring(1, c.length); }
        if (c.indexOf(name) === 0) { return c.substring(name.length, c.length);}
      };
    },
    createCookie: function(name, value, days) {
      var expires = "";
      if (days) {
        var date = new Date();
        date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
        expires = "; expires=" + date.toGMTString();
      }
      var cookie_string = name + "=" + value + expires;
      cookie_string += "; domain=" + (this.cookieDomain.length ? this.cookieDomain : window.location.hostname);
      cookie_string += "; path=" + (this.cookiePath.length ? this.cookiePath : '/');
      if (this.cookieSecure) {
        cookie_string += "; secure";
      }
      document.cookie = cookie_string;
    },
    capture: function() { //Run through parameters array and set cookies for all identified URL parameters
      for (var i = this.parameters.length - 1; i >= 0; i--) {
        parameter = this.parameters[i];
        var value = this.getParameterByName(parameter);
        if ( value !== null && value !== "") {
          this.createCookie(parameter, "", -1);
          this.createCookie(parameter, value, this.cookiePersistDays);
        }
      };
    },
    set: function(name, value) {  //Manually set cookie
      if (name !== null && name !== "" && value !== null && value !== "") {
        this.createCookie(name, "", -1);
        this.createCookie(name, value, this.cookiePersistDays);
      }
    }
  }

  $(document).ready(function() {
    //Cookie Handler
    app.captureCampaign.parameters = ['campaign_source', 'campaign_term']
    app.captureCampaign.capture();
  });
}(jQuery, app.custom));

This looks really intriguing...
What would an example referral link look like? I'm struggling to work it out. Thanks for any advice :-)