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: CST Caesar Tire 20 x 1.75 Blk Wire Bead
Product description: CST Caesar Tire 20 x 1.75 Blk Wire Bead Tire Use: BMX Color Tread/Side: Black/Black Tire Type: Clincher Tire Diameter: 20" ISO Width: 46 mm ISO Diameter: 406 Tire Bead: Steel PSI: 35 - 65 PSI Weight: 500.0 g
Product feature: CST Caesar Tire 20 x 1.75 Blk Wire Bead, ISO Diameter: 406 ISO Width: 46 mm, PSI: 35 -65 PSI 60 tpi casing
Product brand: CST
Target attributes: Size
Answer: attribute: size
value: 20 x
source: product title
attribute: size
value: 20 x
source: product feature
attribute: size
value: 20 x
source: product description