Wozniak of supermemo has found correlation between sleep (recency, debt) and flash card skill.<ref>supermemo.guru/wiki/Sleep_and_learning#Studying_sleep_and_learning_with_SuperMemo</ref><ref>supermemo.guru/wiki/Biphasic_life#Biphasic_learning</ref><ref>supermemopedia.com/wiki/SleepChart</ref> Here alertness corresponds to recall. | Wozniak of supermemo has found correlation between sleep (recency, debt) and flash card skill.<ref>supermemo.guru/wiki/Sleep_and_learning#Studying_sleep_and_learning_with_SuperMemo</ref><ref>supermemo.guru/wiki/Biphasic_life#Biphasic_learning</ref><ref>supermemopedia.com/wiki/SleepChart</ref> Here alertness corresponds to recall. |