Edgar Rice Burroughs books in order
41 books in the catalogue, about 166 hours of reading in all; the shortest takes 2 hours and the longest 7 hours.
5 series and 7 standalone books in the catalogue.
Barsoom
12 books 1 
A Princess of Mars 3.2 h 
The Gods of Mars 3.7 h 3 
The Warlord of Mars #3 2.6 h 4 
Thuvia, Maid of Mars 3.2 h 5 
The Chessmen of Mars 4.3 h 
The Master Mind of Mars 2.7 h 7 
A Fighting Man of Mars 4.2 h 
Swords of Mars 4.2 h 
John Carter of Mars 2.3 h
A Princess of Mars 3.2 h The Warlord of Mars length not known
2 The Gods of Mars 3.7 h 3 The Warlord of Mars #3 2.6 h 4 Thuvia, Maid of Mars 3.2 h 5 The Chessmen of Mars 4.3 h The Master Mind of Mars 2.7 h 7 A Fighting Man of Mars 4.2 h Swords of Mars 4.2 h Synthetic Men of Mars length not known
Llana of Gathol length not known
11 John Carter of Mars 2.3 h Tarzan
32 books 1 
Tarzan of the Apes 2.2 h 2 
The Return of Tarzan 4.6 h 3 
The Beasts of Tarzan 3.9 h 4 
The Son of Tarzan 4.8 h 5 
Tarzan and the Jewels of Opar 3.8 h 
Tarzan the Untamed 5.3 h 8 
Tarzan the Terrible 5.2 h 
Tarzan, Lord of the Jungle 3.5 h 
Tarzan at the Earth's Core 4.0 h 
Tarzan Triumphant 4.0 h 
Tarzan and the Lion Man 3.8 h 
Tarzan and the Forbidden City 3.5 h 21 
Tarzan the Magnificent 3.5 h 22 
Tarzan and the Foreign Legion 3.5 h 23 
Tarzan and the Madman 2.9 h 
The Dark Heart of Time 7.3 h
Tarzan of the Apes 2.2 h 2 The Return of Tarzan 4.6 h 3 The Beasts of Tarzan 3.9 h 4 The Son of Tarzan 4.8 h 5 Tarzan and the Jewels of Opar 3.8 h 6 Jungle Tales of Tarzan length not known
7 Tarzan the Untamed 5.3 h 8 Tarzan the Terrible 5.2 h The Adventures of Tarzan length not known
9 Tarzan and the Golden Lion length not known
10 Tarzan and the Ant Men length not known
The Eternal Lover length not known
11 Tarzan, Lord of the Jungle 3.5 h Tarzan and the Tarzan Twins length not known
12 Tarzan and the Lost Empire length not known
13 Tarzan at the Earth's Core 4.0 h 14 Tarzan the Invincible length not known
15 Tarzan Triumphant 4.0 h 16 Tarzan and the City of Gold length not known
17 Tarzan and the Lion Man 3.8 h 18 Tarzan and the Leopard Men length not known
19 Tarzan's Quest length not known
20 Tarzan and the Forbidden City 3.5 h 21 Tarzan the Magnificent 3.5 h 22 Tarzan and the Foreign Legion 3.5 h 23 Tarzan and the Madman 2.9 h 24 Tarzan and the Castaways length not known
Tarzan and the Valley of Gold length not known
Tarzan: The Lost Adventure length not known
The Dark Heart of Time 7.3 h Tarzan: The Greystoke Legacy length not known
Tarzan: The Epic Adventures length not known
Pellucidar
8 books At the Earth's Core length not known
Pellucidar 3.3 h 
Tanar of Pellucidar 5.7 h Tarzan at the Earth's Core 4.0 h 
Back to the Stone Age 4.2 h 
Land of Terror 6.5 h 
Savage Pellucidar 5.6 h 
Mahars of Pellucidar 4.2 h Amtor
5 books
Pirates of Venus 3.4 h 
Lost on Venus 3.5 h 3 
Carson of Venus 3.6 h Escape on Venus length not known
The Wizard of Venus 3.4 h Caspak trilogy
3 books
The Land That Time Forgot 4.0 h 
Out of Time's Abyss 2.5 h The People That Time Forgot length not known
