Instruction: First, identify the target attributes from the provided list. Then, scan the product title, description, feature, and brand to extract the values associated with each target attribute. Finally, create a list of dictionaries, each containing the extracted attribute, its corresponding value, and the source where it was found.

Input:
Product title: Calvin Klein Men's Xtreme Slim Fit Dot Print
Product description: Calvin Klein xtreme slim fit long sleeve dress shirt with stretch
Product feature: 96% Cotton, 4% Spandex, Imported, Machine Wash, Spread collar, Regular cuff, No pocket, Package Dimensions: 13.4 x 8.4 x 1.9 inches, Shipping Weight: 6.4 ounces, ASIN: B0169AX8GM, Item model number: 33K2897, Date first listed on Amazon: December 6, 2015, Average Customer Review: 4.5 out of 5 stars 2 customer reviews
Target attributes: Neckline
Answer: attribute: neckline
value: spread collar
source: product feature
attribute: neckline
value: dress shirt
source: product description