NID! Cross Blue (same as Pelikan 4001 Royal Blue?) : r/fountainpens
Pelikan 4001 Royal Blue Ink - 62.5 ml Bottle | JetPens
Pelikan 4001 Konigsblau (King's Blue, Royal Blue)) - Ink Reviews - The Fountain Pen Network
Pelikan 4001 Royal Blue 62.5ml Ink Bottle - Pen Boutique Ltd
Pelikan 4001 Brilliant Royal Blue Ink Cartridges - oblation papers & press
Gentleman Reviewer – Mostly focused on product reviews of fountain pens, mechanical pencils, writing materials, bags, everyday-carry, knives, tea, coffee, and anything else I can get my hands on!
1960's Design PELIKAN 4001 royal blue # 78 ink pot glass bottle in original box | eBay
Pelikan Royal Blue | Fountain pen blog
Pelikan 4001 Royal Blue Ink Sample (3ml Vial) - Anderson Pens, Inc.
Pelikan Royal Blue - Ink Sample - The Goulet Pen Company
Pelikan 4001 Royal Blue Ink - 62.5 ml Bottle | JetPens