Amazon.com : AODELAN Camera Remote Control Wireless Shutter Release for Sony a5100, a6000, a6300, a5000, a7 III, a7 II, a7, a7R III, a9, RX100 III, RX10M2, Replaces Sony RM-L1AM and RM-SPR1 :
Star Eater: Documentation of an Issue with the Sony Cameras for Astrophotography (and How to Fix It) – Lonely Speck
Sony A7 III Tutorial - Aperture, Shutter Speed, Manual Mode & Bulb Mode - YouTube
Sony mirrorless camera lost bulb mode - YouTube
Mode BULB chez Sony : où le trouver ?
sony a7iii/A7R3/A9 getting into bulb mode (no silent shutter !) and quickly get exposure time - YouTube