The graphic design of Proof (art director: Kim Sung-jin, HuskyFox) uses typographic quotation marks as visual motifs:

The Proof album came in multiple physical versions. If you are looking for "CD Only," you are likely a collector who:

The Proof CD photobook and lyric booklet use 따옴표 for:

The standard CD version of "Proof" was released with a specific packaging feature known as the "Ttaompyo" (Stamp/Mark) system.

Several songs on Proof have titles officially enclosed in double quotation marks in Korean and English materials, e.g.:

These marks indicate:

This is the full specification for the physical CD album that contains the "Ttaompyo" random cover feature:

1. Packaging Components:

2. Photobook & Visuals:

3. Inclusions (First Press / Standard):