Instruction: Using the product's title, description, features, price, and brand, identify and retrieve the values associated with a specified set of target attributes. Output the extracted values along with their respective sources (e.g., title or feature) indicating where each value was found.

Input:
Product title: Memorex 4.7GB/8x DVD-R (50-Pack Spindle)
Product description: 8x max write speed / 50 discs in spindle pack / Designed for DVD-R recordable drives / 4.7GB storage capacity
Product feature: Supports 8x burning speeds, Media can be written once only, 4.7 GB of storage space (120 minutes of DVD video), For use with DVD-R DVD Recordable drives
Product brand: Memorex
Target attributes: Capacity
Answer: attribute: capacity
value: 4.7gb
source: product title
attribute: capacity
value: 4.7gb
source: product description
attribute: capacity
value: 4.7 gb
source: product feature