The first 2 years: PSP has sold better in the US than PS1, DS, more | Engadget
sales share of consoles in 4th generation onwards, in N. America/Europe/Japan regions (notice how stronger Xbox is in N. America) : r/xbox
PS Vita being outsold by the PSP in Europe too | eTeknix
PS Vita vs 3DS. Is The 3DS Winning The Handheld War? - Wololo.net
Games: Nintendo – the winner takes it all – eurotechnology.com
Exclusive: Sony PSP Versus Nintendo DS - The Sales Showdown
PS4 vs DS – VGChartz Gap Charts – June 2019 Update
Exclusive: Sony PSP Versus Nintendo DS - The Sales Showdown
PSP VS DS Graphics Comparison | N4G
Looking back at 2009 console sales and ahead to 2010 trends | Ars Technica
PS Vita: Sales, Market Share and the 3DS | TheSixthAxis
Graph-Age: Worldwide NDS & PSP cumulative monthly sales & shipments by region! | Page 4 | NeoGAF
RIP, PSP: What the Vita can learn from Sony's late, great handheld - CNET
PlayStation Portable - Wikipedia
PlayStation Portable | Video Game Sales Wiki | Fandom
Switch vs DS Sales Comparison – DS Lead Grows May 2020
Nintendo 3DS Reaches 5 Million In Japan, Breaks Record - Siliconera
Apple slams PSP, DS at iPhone/iPod conference - GameSpot
PSP lifetime unit sales by region 2022 | Statista
Nintendo's Numbers: The State Of The Industry
You Decide: Sony PSP or Nintendo 3DS? | HowStuffWorks
Who won? First-week sales of PS Vita vs. PSP vs. 3DS vs. DS (infographic) | VentureBeat
Financial Results Briefing for Fiscal Year Ended March 2011
Nintendo's Switch to Success: 20 Years of Nintendo Console Sales
3DS vs PSP – VGChartz Gap Charts – October 2018 Update
Semi-Annual Financial Results Briefing for Fiscal Year Ending March 2012
