File:Helium discharge tube.jpg

Please select "one" of your favorite license. English Gas discharge spectrum for helium

Please select "one" of your favorite license. English Helium glowing in a gas discharge tube

Please select "one" of your favorite license. English Xenon gas discharge tube Bangla জেনন গ্যাস ডিসচার্জ টিউব Spanish Tubo de descarga del gas xenón

Please select "one" of your favorite license. English Krypton discharge tube Arabic أنبوب تفريغ حاوٍ على الكريبتون، الطول تقريباً 20 سم، الجهد: 1.8 كيلوفولت،

Please select "one" of your favorite license. English Argon glowing in a gas discharge tube