Method "addJqueryLibrary" is not defined in "Magentothem_Upsellslider_Model_Layout_Generate_Observer"

#0 /home/watchwin/public_html/app/code/core/Mage/Core/Model/App.php(1360): Mage::throwException('Method "addJque...')
#1 /home/watchwin/public_html/app/code/core/Mage/Core/Model/App.php(1337): Mage_Core_Model_App->_callObserverMethod(Object(Magentothem_Upsellslider_Model_Layout_Generate_Observer), 'addJqueryLibrar...', Object(Varien_Event_Observer))
#2 /home/watchwin/public_html/app/Mage.php(448): Mage_Core_Model_App->dispatchEvent('controller_acti...', Array)
#3 /home/watchwin/public_html/app/code/core/Mage/Core/Controller/Varien/Action.php(351): Mage::dispatchEvent('controller_acti...', Array)
#4 /home/watchwin/public_html/app/code/core/Mage/Cms/Helper/Page.php(113): Mage_Core_Controller_Varien_Action->generateLayoutBlocks()
#5 /home/watchwin/public_html/app/code/core/Mage/Cms/Helper/Page.php(52): Mage_Cms_Helper_Page->_renderPage(Object(Mage_Cms_IndexController), 'ma_bachas4_home')
#6 /home/watchwin/public_html/app/code/core/Mage/Cms/controllers/IndexController.php(45): Mage_Cms_Helper_Page->renderPage(Object(Mage_Cms_IndexController), 'ma_bachas4_home')
#7 /home/watchwin/public_html/app/code/core/Mage/Core/Controller/Varien/Action.php(418): Mage_Cms_IndexController->indexAction()
#8 /home/watchwin/public_html/app/code/core/Mage/Core/Controller/Varien/Router/Standard.php(254): Mage_Core_Controller_Varien_Action->dispatch('index')
#9 /home/watchwin/public_html/app/code/core/Mage/Core/Controller/Varien/Front.php(172): Mage_Core_Controller_Varien_Router_Standard->match(Object(Mage_Core_Controller_Request_Http))
#10 /home/watchwin/public_html/app/code/core/Mage/Core/Model/App.php(365): Mage_Core_Controller_Varien_Front->dispatch()
#11 /home/watchwin/public_html/app/Mage.php(684): Mage_Core_Model_App->run(Array)
#12 /home/watchwin/public_html/index.php(83): Mage::run('', 'store')
#13 {main}