Instruction: Parse the product information to locate the target attribute, and then provide the extracted value of the target attribute and its source in the output, specifying None if the attribute is not present.

Input:
Product title: Cattior Womens Bow Flax Summer Slippers Outdoor Slippers
Product description: House slippers The most popular slippers this year,And,send family, send friends . Shipping time :In generally,customers can receive this slipper about 10-18 working days.
Product feature: cotton, Rubber sole, Bedroom slippers, Indoor sole, Fitment: True to Size, Hand or machine wash, Cozy and comfortable slippers, Shipping Information: View shipping rates and policies, ASIN: B01DKEI3YM, Date first listed on Amazon: March 27, 2016, Average Customer Review: 3.5 out of 5 stars 3 customer reviews
Product price: $15.99
Product brand: Cattior
Target attributes: Heel Style
Answer: attribute: heel style
value: None
source: None